The Laureen Rahn case appeared to be a straightforward analysis. There was enough information about Laureen’s character and behavior to contribute to a victimology assessment, and a fair accounting of her last known activities. But halfway through the ACH matrix, it became clear that the available evidence was not strong enough to distinguish between multiple hypotheses. The TRACE Technique, a novel methodology for low- to no-evidence cases, appeared better suited to the task. Ultimately, however, TRACE 1.3 also failed to produce sufficiently reproducible results to support a confident ranking of the hypotheses. Instead, the analysis exposed further weaknesses in an ongoing effort to develop a methodology for low- to no-evidence cases.
Methodology and Scope
This case study is an educational demonstration of structured intelligence analysis using publicly available information. It is not an official investigative finding and reflects the evidence available at the time of publication. Conclusions are provisional and may change as new evidence becomes public. See the full methodology note at the end of this analysis.
The TRACE Technique is an experimental analytic framework developed for low- to no-evidence cases. It remains under development and is being refined through application to actual unsolved cases. Its utility has not yet been established. This analysis was conducted using TRACE 1.3, the version current at the time of analysis.
Introduction
Fourteen-year-old Laureen Rahn disappeared from her home in Manchester, New Hampshire, on the night of 26 April 1980.* Explanations for her disappearance ranged from her being a teenage runaway to foul play, with narratives about sexual exploitation introduced over time. Decades later her case remains unsolved.
*(Analyst’s note: Contemporaneous accounts reported that Laureen was last seen at approximately 11:45 PM on 26 April 1980. Later accounts place the last known sighting at approximately 12:30 AM on 27 April 1980. This analysis uses the contemporaneous reporting unless otherwise noted.)
Laureen Ann Rahn
Laureen Ann Rahn lived with her mother, a single parent, on the third floor of a six-unit apartment building in Kalivas-Union, a neighborhood south of downtown Manchester, New Hampshire. While she was described as a good student with a broad support system of extended family members who lived nearby and a mother-daughter relationship characterized as “the best of friends,”1 Laureen had challenges. One of her several aunts said there was a period in which Laureen had “hung around with the wrong people.”2 She frequently drank alcohol and was an occasional user of marijuana.3 She was afforded the freedom to “run much of her own young life,” although officials at her junior high said “it was a freedom Laureen did not abuse.”4
26 — 27 April 1980
On the day she disappeared, Laureen received permission to skip a tennis tournament she and her mother planned to attend in northern New Hampshire in which her mother’s boyfriend, a “local tennis pro,” was participating.5 Laureen told her mother she preferred to stay home with friends. There had been a “small disagreement” between the two that morning, but her mother reported it was of little consequence [NFI].6
Laureen spent “much of the day and evening” at a regular hangout, the Rosebud Superette, a small convenience store located catercorner to her house. One friend said Laureen was seen restocking shelves with beer and wine coolers.7 At some point, she was also observed “drinking beer in a doorway with a couple of older boys.”8
The events of the evening, the persons involved, along with the ages of those persons, and the timeline itself shifted between press accounts. What appears to be most consistently reported is that Laureen was in the company of a female friend, who was also 14, and at least one male of an indeterminate age. (Analyst’s note: Laureen had a boyfriend, but he had been grounded for a month,9 so he was not the male who had been present on the evening Laureen disappeared.) The group arrived at Laureen’s apartment sometime after 11 PM. They had obtained alcohol–the circumstances surrounding how they obtained it are also disputed–and proceeded to drink.
Around 11:45 PM,10 the male guest heard voices on the hallway stairs. Believing it was Laureen’s mother returning home, and fearing he would get into trouble for being there so late, he left the apartment through the rear exit. The unidentified male later told Laureen’s mother he “heard Laureen lock the back door behind him.”11 This was the last confirmed place and time in which Laureen was seen.
Her mother arrived home around 12:45 AM12 to find the hall lights in the building out and the front door unlocked.13 Her concern grew when she found the back door also unlocked and ajar. Laureen’s girlfriend was asleep in her bed. When awakened, she said Laureen had planned to spend the night on the couch. Reports are there was a “pile” of Laureen’s clothing on the couch14 and possibly a blanket and pillow.
There had been no signs or sounds of a struggle and neighbors later said they saw no one enter the building.15 Police were notified of Laureen’s disappearance around 3:45 AM.
Reddit Post, circa 2013/14
(Analyst’s note: Several of the details of the following post could be extrapolated and appeared to fit individuals whose names, ages, and locations matched known details of the case. The original source of the material, Laureen’s 14-year-old friend, had excellent placement, however the account below comes secondhand, and in one instance thirdhand. This qualifies as a “[Tier 2] Secondary/credible-but-unverified” source.)
An uncorroborated account was published on the forum Reddit circa 2013/14 (“12y ago”). The post came from an unidentified individual who claimed to be the daughter of the female friend with whom Laureen spent her last evening. The poster said Laureen and the friend had planned a sleepover at Laureen’s house. The girls, both 14,16 reportedly met two males, identified as 18 and 21. The poster said the 18-year-old had obtained the beer. In a thirdhand account (the poster’s father got the information from the poster’s mother), Laureen later “left with one of the guys.”
This is the only known account that places two males in the apartment that night. In an article from 2020, another of Laureen’s aunts (not the one previously quoted) said the party consisted of “two friends, a girl her age and a 21-year-old man.”17 A story from 1990 calls the male friend “a 15-year-old boy.”18 Thus, while the Reddit account potentially provides a significant detail about Laureen’s final evening, the number and identities of the male companions are not consistently reported across sources.
Three Unexplained Telephone Charges
Seven months after Laureen’s disappearance, the case veered into a new direction when Mrs. Rahn found three unexplained charges on her November telephone bill. The calls were placed on 1 October 1980 and occurred 10 and 15 minutes apart. All originated in Santa Monica, California.
Mrs. Rahn reached out to Santa Monica Police and found two of the calls came from a pay phone in a Santa Monica motel, and one from a pay phone in a restaurant across the street from the motel. Two of the calls were connected to a motel in Santa Ana, California, and the third to a hotline, reportedly for teenagers with questions about sex.19
Mrs. Rahn telephoned the hotline number and found it was run by a physician who denied knowing anything about the call.
It appears law enforcement was working the case less actively at this point, so private investigators and organizations stepped in.
In 1985, the physician was again contacted. He said sometimes runaways visited his wife at their home, and one of the young women “may have” been from New Hampshire. The information was never corroborated, and he did not elaborate.
In 1986, an individual working on behalf of Mrs. Rahn obtained additional details about the motels associated with the calls. “Authorities” [NFI] said one “may have” been used by a child pornographer known only as “Dr. Z.” Dr. Z was not linked to the physician who ran the hotline. It was never established that child sexual images were involved in Laureen’s disappearance.20
Manchester police said they had no record of the calls in their files–they had never been notified of the results of the investigations, which had been handled privately.
Some later accounts of Laureen Rahn’s disappearance emphasize a sexual exploitation narrative. It is necessary to separate what is known and not known, established, substantiated, and hypothesized:
What is known: (1) Three calls originating in California were billed to the Rahns’ November 1980 telephone bill; (2) the calls were associated with Santa Monica and Santa Ana pay phones; (3) one call was associated with a teen sexual-assistance hotline.
What is not established: (1) Laureen made the calls; (2) Laureen was in California; (3) Laureen contacted the hotline; (4) “Dr. Z” was connected to the hotline physician.
What is not substantiated: (1) The hotline physician encountered Laureen; (2) the physician’s wife encountered Laureen; (3) Laureen was involved with runaway girls/sexual exploitation; (4) Laureen was connected to “Dr. Z.”
What is hypothesized, yet untested and unproven: (1) Laureen was trafficked/exploited in California.
Analysis
Analysis of Competing Hypotheses (ACH)
The analysis began with a classic ACH matrix. However, it soon became clear the available facts and circumstances were neither strong nor distinctive enough to differentiate between hypotheses. So, the analysis pivoted to The TRACE Technique. TRACE is designed for low- to no-evidence cases. It shifts the focus of the analysis away from what, why, or how something happened, to which hypothesis best reconciles with known facts or evidence patterns, and then factors in probability, opportunity, and logistics.
The TRACE Technique 1.3
PHASE 1: Hypothesis Generation
H1: Environmental accident/misadventure (Laureen left the apartment voluntarily on foot at which point she suffered an accidental or environmental event.)
H2: Known person/ordinary social encounter that turned violent (Laureen encountered someone within her existing social orbit–at the Superette, while walking, or elsewhere–and the encounter unexpectedly became violent.)
H3: Voluntary ride/controlled transition to another location (Laureen voluntarily entered a vehicle with someone she recognized or trusted, intending to go somewhere else, and the situation subsequently became dangerous or violent.)
H4: Voluntary disappearance/runaway (Laureen left the apartment voluntarily with the intention of separating herself from her existing circumstances, either temporarily or permanently.)
H5: Opportunistic predation/abduction (Laureen was approached by an unknown person who exploited an opportunity to abduct or otherwise control her, either near the apartment, on the street, or at another location.)
H6: Alcohol-related accidental death with concealment (Laureen died accidentally in the course of drinking–most plausibly by aspiration of vomit or positional asphyxia while unconscious, or by respiratory depression from acute alcohol poisoning. A secondary variant admits a fall or head injury sustained while intoxicated. Whoever was present had reason to fear the consequences of summoning help.)
H7: Voluntary encounter with an unknown person (Laureen voluntarily interacted with an unknown person and the encounter subsequently became dangerous or fatal.)
PHASE 2: Reconciliation with facts
A. Base-rate Research: How often does each hypothesis actually occur in similar circumstances? Consider statistical frequency, comparable cases, regional/environmental factors.
B. Case-specific Facts: What do we know with certainty about this incident? Consider timeline precision, location characteristics, victim profile and behavior patterns, relationship context, physical evidence (if any).
C. Evidence Expectations: For each hypothesis, what physical evidence should exist if this scenario actually occurred?
H1: Environmental accident/misadventure (Laureen left the apartment voluntarily on foot at which point she suffered an accidental or environmental event.)
A. Base-rate Research
Urban hazards, in combination with intoxication, could lead to disappearance/death:
- Unused or abandoned buildings/construction sites
- Inherent structural instability; unprotected openings [basements, elevator shafts]; utility pits; construction trenches
- If construction resumes before body is found, remains can be buried under heavy earth, concealing them permanently
- Inherent structural instability; unprotected openings [basements, elevator shafts]; utility pits; construction trenches
- Waterways/drainage hazards
- Drainage networks featuring large intake pipes running beneath streets
- Runoff can carry body deep into storm sewer network and into larger river systems before search is initiated
- Drainage networks featuring large intake pipes running beneath streets
- Riverbanks and steep embankments (Merrimack River)
- High, slippery spaces; missteps due to intoxication
- Cold water shock/incapacitation, then currents, undertows, submerged debris, structural pilings that trap remains underwater or transport far downstream, preventing surface recovery
- High, slippery spaces; missteps due to intoxication
No statistics could be located that addressed child fatalities in 1980, however other years were available: (1) The New Hampshire Child Fatality Review Committee “Second Annual Report,” issued in October 1999, and (2) The US Department of Health and Human Services/Centers for Disease Control and Prevention, “Mortality Among Teenagers Aged 12-19 Years: United States, 1999-2006,” issued in May 2010. (Analyst’s note: The tables on New Hampshire Child Fatality Review Committee “First Annual Report” were printed in uneven columns that prevented the data from being interpreted correctly. Therefore, the Second Annual Report was used as a reference for the New Hampshire statistics.
- New Hampshire had 176 child fatalities in 1995. Of these, seven were females broadly described as between the ages of one and 14.
- For reference, in 1996, there were 162 child fatalities; four were females aged one to 14. In 1997, there were 134 child fatalities; nine were females aged one to 14. In 1998, there were 199 child fatalities; four were females aged one to 14. In 1999, there were 143 child fatalities; five were females aged one to 14. Therefore, over a five-year period, slightly fewer than six girls per year, aged one to 14, died as a result of accidents.
- Nationally, the CDC found that between 1999 and 2006, the death rate for 14-year-old females was 20 per 100,000.
B. Case-specific Facts:
- Per the New Hampshire Child Fatality Review Committee: Cause of death was not divided by sex, but the ages were more narrowly defined. Laureen fell into the category of youths between 10 and 14. Few of the causes of unintentional death could be categorized as “environmental accident/misadventure,” but they were as follows: motor vehicle crash-1; motor vehicle/pedestrian-1; drowning-2; fire-1; cut/pierce-1; other-1. Falls were included as a category, but no falls were recorded during the period studied.
- Per the CDC: The leading cause of death among all teens was accidents, with the majority, 73 percent, motor vehicle traffic accidents. Unintentional drowning accounted for five percent of cases; other land transport accidents accounted for three percent.
C. Evidence Expectations:
Depending on the type of accident, any of the following may be expected to be seen:
- remains/body (immediately or over time)
- witnesses
- clothing or personal effects at/near the accident site
- reports of searches
- vehicle/pedestrian evidence (if transportation were involved)
- alternatively, no evidence at all if the accident occurred in an inaccessible or concealed location
No unidentified bodies have been reported in publicly available sources in the greater Manchester, New Hampshire, area from 1980 until today. The New Hampshire Department of Justice had only one unidentified victim on its Web site, “Jane Doe Hopkinton,” a 13- to 18-year-old adolescent female, but who appears to have gone missing sometime before 1930. A search of NamUs found two unidentified juvenile females, one from Los Angeles, California, and another from Iola, Texas, but none from New Hampshire. A search of the Doe Network for unidentified juvenile females was negative.
Should an accident have befallen Laureen, the most obvious evidence would likely have been the body itself; however, as set forth in the research portion of this section, there were circumstances that could result in a person going missing and never being recovered.
H2: Known person/ordinary social encounter that turned violent (Laureen encountered someone within her existing social orbit–at the Superette, while walking, or elsewhere–and the encounter unexpectedly became violent.)
A. Base-rate Research:
The FBI Crime Data Explorer collected historic data for homicides handled by the Manchester Police Department, but 1985 was the earliest year covered. In its place, data from January 1985 to December 1994 were collected. (Analyst’s note: It is acknowledged localized homicide rates can fluctuate year-to-year. These calculations should be viewed as estimations for the purpose of the matter at hand, not definitive data points.)
- Youth Victim Proportion: During this 10-year timeframe, there were 38 homicides; 5.26% (2 of the 38) fell into the 10–19 age bracket. The data did not cross-reference age and sex, so it was unknown if the two victims were male or female. For reference, 15 of the 38 victims were female.
- Acquaintance Offender Proportion: Approximately 18.42% (7 out of 38) of the total homicides were committed by acquaintances, about 1 out of every 5 cases.
Assuming a total population of Manchester, New Hampshire, of approximately 97,000 during this time period, the annual youth homicide rate would be about .2 per year, with the acquaintance homicide rate about .7 per year.
Case-specific Facts:
Laureen appeared to gravitate toward social opportunities. She had been drinking earlier with two older boys at the Superette. She was in her apartment with two other friends; one planned on spending the night. One of her many aunts described her as “very outgoing.”21
Evidence Expectations:
Disposal: This would more likely be a case of panic disposal. Panic disposals generally take place near the site of the event as the perpetrator(s) simply seeks to resolve an emergency. Therefore, the dump site would be a location that could be accessed quickly with minimal effort. The disposal would not involve special tools because of its spontaneity.
This scenario does not imagine Laureen moving far outside of her neighborhood (no vehicles involved), so it would likely involve nearby, opportunistic disposal.
H3: Voluntary ride/controlled transition to another location (Laureen voluntarily entered a vehicle with someone she recognized or trusted, intending to go somewhere else, and the situation subsequently became dangerous or violent.)
A. Base-rate Research:
The closest statistic that could be found that addressed the “controlled transition to another location,” referred to “non-family abduction,” which may be one aspect of this scenario, although it is not a solid match. There is a degree of crossover between this hypothesis and H2, an encounter with a known friend.
The First National Incidence Studies of Missing, Abducted, Runaway, and Thrownaway Children (NISMART-1) reported that in 1988, 3,200-4,600 children met the legal definition for non-family abduction. This covers “the coerced and unauthorized taking of a child into a building, a vehicle, or a distance of more than 20 feet; the detention of a child for a period of more than an hour; or the luring of a child for the purposes of committing another crime. Many short-term abductions that took place in the course of other crimes like sexual assault were counted under this definition.”
In its 1984 Uniform Crime Reports, the FBI found 39 percent of homicides were committed by an acquaintance.22
Case-specific Facts:
Laureen’s transportation habits are unknown:
- She didn’t drive;
- She was socially active;
- She had been drinking;
- There was an opportunity for her to accept transportation;
- Transportation would dramatically expand the geographic search/disposal problem.
Evidence Expectations:
Witness(es): If this scenario occurred, the primary evidence might be an eyewitness account who saw her get into the car. It was a Saturday night, around midnight, so it’s feasible persons were still milling about. However, the area did not appear to have a great deal of businesses, so eyewitnesses would more likely be neighbors or else friends who still lingered around the Superette.
If she walked a few blocks to the west, less than a mile, she would be in downtown Manchester, an area that would more likely have had potential witnesses. Barring an eyewitness, there would be little other evidence of Laureen accepting a ride as security cameras were rare, and tracking by cell phones non-existent.
Disposal: This hypothesis fell between homicide and an encounter that unexpectedly turned violent: Laureen accepted a ride from someone with whom she felt comfortable, but at some point, the circumstances changed.
Because a car was involved, she could have been transported a distance from where she was last seen. This greatly expands the potential for disposal sites.
If the individual had homicidal tendencies, he could have disposed of Laureen’s body in an area previously scouted and chosen because it offered a good opportunity for concealment. If her death resulted from an accident, it may have been more proximity-driven, simply placed near where the encounter took place with minimal thought or effort beyond expediency.
H4: Voluntary disappearance/runaway (Laureen left the apartment voluntarily with the intention of separating herself from her existing circumstances, either temporarily or permanently.)
A. Base-rate Research:
According to NISMART-1, in 1988, there were 450,700 “broad scope” runaways (any child who intentionally left home without permission and stayed away at least overnight). The report noted, “The runaway problem did not appear to be larger in 1988 than at the time of the last survey in 1975,” so this was a reasonable baseline to use for 1980.
In 2024, the National Runaway Safeline/Crisis Services Snapshot for New Hampshire reported 58 teens reached out for help. Sixty-four percent were female. Three percent were 14 years old. The top concerns were family dynamics, economics, emotional/verbal abuse, and mental health.
Case-specific Facts:
Although friends said she never talked about running away, an aunt said she had mentioned it “more than once.”23 On the night she disappeared, she left her purse, money, and clothing behind, including a coat and a pair of sneakers she’d recently received for her birthday that she regarded as special. If the friends who were with her that evening found her unusually troubled, it was not publicly reported.
Evidence Expectations:
The most compelling evidence Laureen had left home would likely be items missing from the home, those necessary for a prolonged journey, or else items deemed valuable by Laureen. Possibly, she would have left a note, as Mrs. Rahn said Laureen routinely kept her apprised of her movements; or she may have mentioned her plans to the friend who had been invited to spend the night. She probably would have taken money–either money she had saved or else money kept in the house.
H5: Opportunistic predation/abduction (Laureen was approached by an unknown person who exploited an opportunity to abduct or otherwise control her, either near the apartment, on the street, or at another location.)
A. Base-rate Research:
According to the New Hampshire Department of Justice Cold Case Unit and Charley Project, between 1970 and 1989, there were 19 women and girls aged 12 to 25 whose cases remained unresolved (missing/murdered/suspicious death), including Laureen’s. Of those, 10 were teens (13-18); nine were adult women (20-25).
In examining the data geographically, 0 to 10 miles from Manchester, two cases occurred in Manchester itself: Laureen, 14, who disappeared in 1980; and Denise Daneault, 25, who lived just a couple of blocks from Laureen, and also disappeared in 1980. A third victim, Denise Beaudin, 23, disappeared in Goffstown in 1981.
In expanding the distance up to 20 miles from Manchester, there was one case with two victims: Diane Compagna, 15, and Anne Psaradelis, also 15. The girls were hitchhiking together in July 1973, possibly from Hampton Beach back home to Merrimack. Their decomposed remains were found in September 1973 in the woods off New Boston Road, Candia.
Of the 19 cases, the remains of six women were never recovered (including Laureen’s). Two cases that are often mentioned in conjunction with Laureen’s–Denise Daneault and Rachel Garden, both of whom disappeared in 1980–are included in the six cases in which the remains of the victims were never recovered.
The National Crime Survey reporting statistics from 1984 found 18 percent of homicides were committed by strangers.24
Case-specific Facts:
Laureen had a great deal of freedom to make her own decisions, so it would not have been usual for her to have headed back onto the street after midnight, especially on a Saturday night during her school’s Spring Break. The neighborhood was a familiar area, so she may not have been alert to “stranger danger,” a term popularized during that era with the 1979 disappearance of Etan Patz.
Evidence Expectations:
If Laureen were killed by a stranger, one possible expectation would be that her body would eventually be discovered. In a nonrandom national sample25 of 119 homicide cases26 involving body disposal,27 72 percent28 of stranger29 offenders left the victim unconcealed30; bystanders subsequently discovered the bodies in 61 percent)31 of stranger-offender cases. (Analyst’s note: In nearly three-quarters of cases, the remains were found in the offender’s neighborhood, on his property, or on another site connected to him; offenders tend to gravitate toward surroundings that are comfortable to them and familiar.32)
Opportunistic predators sometimes dump bodies along transportation corridors, which are often routes with which they are familiar. If they put effort into hiding the body, there may be evidence of tools or materials that would not be readily available–evidence of planning (shovels, tarps). The victim may be missing items (“souvenirs”) taken from her person and kept. The body may be posed.
H6: Alcohol-related accidental death with concealment (Laureen died accidentally in the course of drinking–most plausibly by aspiration of vomit or positional asphyxia while unconscious, or by respiratory depression from acute alcohol poisoning. A secondary variant admits a fall or head injury sustained while intoxicated. Whoever was present had reason to fear the consequences of summoning help.)
A. Base-rate Research:
(Analyst’s note: Available mortality statistics do not provide a sufficiently granular historical measure of fatal alcohol intoxication among adolescents independent of alcohol-related injuries, making it difficult to establish a reliable base rate for the specific scenario of alcohol poisoning or aspiration following intoxication.)
- The Substance Abuse and Mental Health Services Administration, a branch of the US Department of Health and Human Services, reported excessive drinking resulted in more than 4,300 deaths annually among underage youths. In 2010, underage youths also made approximately 189,000 emergency-department visits involving alcohol. (Analyst’s note: These figures encompass multiple consequences of alcohol use and therefore do not provide a measure of deaths caused by alcohol poisoning or acute intoxication alone.)
- Based on 2012–2014 data, the National Survey on Drug Use and Health ranked New Hampshire second among the 50 states for the percentage of underage youths reporting binge drinking during the most recent month surveyed. (Analyst’s note: Because these data are substantially later than Laureen’s disappearance, they provide contextual information about alcohol use in New Hampshire rather than a direct measure of conditions in 1980.)
Case-specific Facts:
Laureen was reported to have been drinking beer earlier in the day. She was in her apartment that night drinking wine and beer with two friends. She “frequently used alcohol.”33
Evidence Expectations:
Alcohol event: This hypothesis supposes Laureen was in the company of another individual consuming alcohol when an emergency arose. The individual chose to conceal his or her involvement by removing Laureen’s body from the scene and disposing of it. In this case, concealment arose from panic/emotional distress, not criminal intent. (Analyst’s note: This element requires only that whoever was present had reason to fear the consequences of summoning help: at minimum, having furnished alcohol to a minor, and potentially some further circumstance [i.e., legal exposure, drugs on scene, or a relationship he or she would have had to explain.] Under those conditions, panic may have produced an attempt at disposal rather than a call to 911.)
Panic concealment: In the event of panic, the disposal itself would likely show little effort by the perpetrator to find the “perfect” location. Instead, the goal would be to seek a placement close by, accessible, and private. No tools or materials that were not on hand or readily available would be used in the concealment.
H7: Voluntary encounter with an unknown person (Laureen voluntarily interacted with an unknown person and the encounter subsequently became dangerous or fatal.)
A. Base-rate Research:
This category borrows some of the data from H2: Known person/ordinary social encounter that turned violent, but rather than exploring “Acquaintance Offender Proportion,” we factor in “Stranger Offender Proportion.”
- Youth Victim Proportion: Approximately 5.26 percent (2 out of 38) of the total victims fell into the 10–19 age bracket.
- Stranger Offender Proportion: Approximately 23.68 percent (9 out of 38) of the total homicides in Manchester during the period studied were committed by strangers, slightly less than 1 out of every 4 cases.
Assuming a total population of Manchester, New Hampshire, of approximately 97,000 during this time period, the annual youth homicide rate would be about .2 per year, with the stranger homicide rate about .9 per year. (Analyst’s note: It is acknowledged that localized homicide rates can fluctuate significantly from year to year. These calculations should be viewed as estimations for the purpose of the discussion at hand, not definitive data points.)
Case-specific Facts:
What is known: Laureen was outgoing, socially active, free to be outside on her own, was a consumer of alcohol
What is inferred: Laureen may have been comfortable in a local setting (her neighborhood)
What is hypothesized: Laureen may have engaged with an unknown person
Evidence Expectations:
This scenario imagines Laureen encountering a person or persons milling about on the street without access to transportation, or else, an opportunistic neighbor, someone who may have seen her around–but with whom she was not familiar–and invited her in. Both of these circumstances suggest spontaneity, therefore the disposal would likely show little evidence of planning. She would likely be found near her last known location as a panic-driven perpetrator is not likely to engage in long-distance transport.
PHASE 3: Analysis of Competing Explanations
- Evidence Signature Match (ESM): Does base-rate research show this is a real-world, empirically documented scenario, and is the available case information compatible with it? Score: 1-little or no empirical support; scenario is highly unusual or poorly documented (is this even a documented phenomenon?) (add 7); 2-limited support; scenario occurs, but comparable cases are uncommon or substantially different (it happens, but the comparisons aren’t very good) (add 14); 3-plausible and documented; comparable cases exist under circumstances broadly similar to the case (it happens, and there are reasonably comparable circumstances) (add 21); 4-well-documented; comparable cases show the scenario occurring with characteristics reasonably similar to this case (there are good comparable cases) (add 28); 5-strong empirical support; scenario is well-established and closely resembles the circumstances of the case (the characteristics and circumstances closely resemble the case) (add 35)
- Opportunity/Feasibility (O/F): Is this scenario physically and practically possible given the known time, location, access, and circumstances? Score: 1-very poor feasibility (add 6); 2-poor feasibility (add 12); 3-plausible (add 18); 4-good feasibility (add 24); 5-very good feasibility (add 30)
- Logistical Complexity (LC): How much additional action, preparation, coordination, transportation, concealment, cleanup, staging would be required for the hypothesis to produce the observed circumstances? Score: 1-very high complexity; extensive staging, concealment, coordination (add 2); 2-high complexity; several deliberate actions (add 4); 3-moderate complexity; some action required (add 6); 4-low complexity; minimal preparation required (add 8); 5-very low complexity; can happen in place with no preparation (add 10)
- Elimination Factors (EF): Are there specific facts that rule out or severely undermine this hypothesis? [E/F is scored as a penalty; subtract points.] Score: 1-minimal evidence contradicts hypothesis (subtract 5); 2-some evidence undermines hypothesis (subtract 10); 3-moderate evidence contradicts hypothesis (subtract 15); 4-strong evidence contradicts hypothesis (subtract 20); 5-hypothesis effectively eliminated by known facts (subtract 25) (Analyst’s note: I leave room for hedging on this attribute. My ESM scores are more definitive. But for EF, I factor in the possibility of error on the part of investigations/reporting.)
PHASE 4: Tally Results (Matrix)
Fill in the matrix with your results.
| HYPOTHESIS | Evidence Signature Match (ESM) (1-5) (scored 7-35) | Opportunity/ Feasibility (O/F) (1-5) (scored 6-30) | Logistical Complexity (LC) (1-5) (scored 2-10) | Elimination Factors (EF) (1-5) (scored -5 to -25) | Strength Score (ESM + O/F + LC – EF) |
| H1: Environmental accident/misadventure | 14 | 18 | 10 | -20 | 22 |
| H2: Known person/ordinary social encounter that turned violent | 14 | 24 | 6 | -20 | 24 |
| H3: Voluntary ride/controlled transition to another location | 14 | 12 | 6 | -20 | 12 |
| H4: Voluntary disappearance/runaway | 7 | 6 | 6 | -25 | -6 |
| H5: Opportunistic predation/abduction | 28 | 18 | 4 | -15 | 35 |
| H6: Alcohol-related death following voluntary socializing | 35 | 18 | 10 | -15 | 48 |
| H7: Voluntary encounter with an unknown person | 21 | 18 | 6 | -15 | 30 |
Higher scores more closely fit the evidence pattern; lower scores can be effectively eliminated unless additional facts arise in the course of the investigation.
PHASE 5: Findings
As is customary at The Intelligence Shop, the findings of the analyst are compared to the findings of one or more large language models (LLMs), in this case, ChatGPT and Claude. The purpose is to identify a method that can reach some level of consensus between models in order to claim reproducible results. While a full consensus is rare, there is often a partial consensus with enough agreement to come to broad conclusions, or to support or eliminate one or more hypothesis. However TRACE 1.3 did not achieve that goal:
| Hypothesis | Analyst | ChatGPT | Claude |
| H1: Environmental accident/misadventure | 5 | 1 | 5 |
| H2: Known person/ordinary social encounter that turned violent | 4 | 1 | 1 |
| H3: Voluntary ride/controlled transition to another location | 6 | 5 | 4 |
| H4: Voluntary disappearance/runaway | 7 | 4 | 2 |
| H5: Opportunistic predation/abduction | 2 | 3 | 3 |
| H6: Alcohol-related death following voluntary socializing | 1 | 7 | 7 |
| H7: Voluntary encounter with an unknown person | 3 | 6 | 6 |
On one hand, the two LLMs found some consensus:
- ChatGPT and Claude agreed on the first-place ranking of H2, an ordinary social encounter with a known person that turned violent. Although, ChatGPT found H2 tied with H1, environmental accident, a hypothesis that Claude placed fifth.
- ChatGPT and Claude both found H5, opportunistic predator in third place.
- The two LLMs were broadly similar in their assessment of H3, a voluntary ride to a secondary location. ChatGPT placed it fifth; Claude placed it fourth.
- Both LLMs agreed on the last place rankings of H7, voluntary encounter with an unknown person and H6, alcohol-related death.
The human analyst processed the facts and circumstances much differently. The results were sufficiently divergent that it was not possible to draw even broad conclusions. (Analyst’s note: The Judy Bradford Smith case produced a similar result. The human-led analysis led to an outlier conclusion about a dissociative state as the catalyst for Judy’s travel to North Carolina. This divergence suggests that humans and LLMs may weigh data differently, even when presented with the same set of information.)
- The hypothesis ranked first by the human analyst, an alcohol-related death following voluntary socializing, was placed last by the two LLMs.
- The hypothesis most favored by the two LLMs, an ordinary social encounter that turned violent, was placed mid- to low-level by the analyst.
- The “closest” result–somewhat devalued by the rest of the findings–was an encounter with an opportunistic predator. This placed in the top three in all three analyses.
TRACE 1.3 did not produce nearly the hoped-for results in the latest iteration of The TRACE Technique in an ongoing effort to identify a methodology suitable for analyzing low- to no-evidence cases.
What went wrong?
Low- to no-evidence cases are a frequent theme in unsolved crimes. Classic analytical methodologies, such as ACH, work well when there is evidence to test, such as in the Hugues de la Plaza analysis. But when there are no forensics or witnesses, the circumstances are vague, the body is absent, and the hypotheses are multitudinous, currently recognized analytical techniques fall short. Hence the need for a reproducible formal methodology for analyzing these types of cases.
The TRACE Technique was designed for and is currently being tested to fill this gap. TRACE shifts the focus of the analysis away from what, why, or how something happened, to which hypothesis best reconciles with known facts or evidence patterns, and then factors in probability, opportunity, and logistics. But its utility remains inconsistent. The first iteration, the Amy Wroe Bechtel disappearance, appeared to yield the “strongest” result, although it was only tested by the human analyst and one LLM. The second and third iterations of TRACE–as applied to the Mitchel Weiser/Bonnie Bickwit and Laureen Rahn matters, respectively–led to less satisfactory results. In looking at all three cases, we can identify a few problems that need to be addressed as we proceed to TRACE 1.4:
Problem: All versions of TRACE rely heavily on subjectivity. Solution: Continue exploring methods to reduce and constrain subjectivity, including the possible use of objective probability estimates.
Problem: All versions of TRACE use weighted elements, but the weight assigned to each element remains in dispute. Solution: Test alternative weighting schemes systematically, and modify weights only between projects–not during an active analysis.
Problem: The Amy Wroe Bechtel case appeared to yield the strongest result. One of the leading factors that appeared to distinguish it from the others was the environment in which Amy Wroe Bechtel was last seen. Solution: Conduct a comparative analysis of the cases used to test TRACE. Examine environmental, temporal, geographic, transportation, witness, and other constraints that may have contributed to stronger or weaker results.
Problem: In the course of working the current matrix, it was determined some of the definitions, particularly involving the ESM score, were unclear. Adjustments were made to the language even as the analysis was being conducted. Solution: Commit to the present methodology; make adjustments in the next iteration.
Problem: Some hypotheses in the Rahn case overlapped or were insufficiently differentiated. Solution: Identifying clear, distinguishable hypotheses continues to be a cornerstone of intelligence and crime analysis. Each hypothesis should be unique and comprehensive. If mid-analysis revisions become necessary, start a fresh matrix.
About These Case Analyses
The case studies published on The Intelligence Shop are educational exercises intended to demonstrate structured analytical techniques, including Analysis of Competing Hypotheses (ACH), evidence evaluation, and confidence assessment.
These analyses are based on publicly available information, including official records, court documents, publicly released investigative materials, reputable media reporting, and other open-source information available at the time of publication. They do not rely on privileged investigative files, nonpublic evidence, witness interviews, or other information available only to law enforcement or the courts.
An intelligence analyst and a criminal investigator perform different functions. Investigators gather evidence. Analysts evaluate available evidence to assess the relative strength of competing explanations. Accordingly, the conclusions presented here are analytical assessments—not official findings—and are limited by the scope and quality of the publicly available record.
Analytical assessments are inherently provisional. As new evidence becomes publicly available or previously unavailable information comes to light, an assessment may change. Revisions are made when warranted by credible evidence.
The purpose of these posts is not to declare definitive truth, but to demonstrate transparent, evidence-based reasoning. Readers who identify factual inaccuracies or wish to provide additional publicly verifiable information are welcome to contact the author through the Web site.
Footnotes
- Shawne K. Wickham, “Mom’s plea: Laureen, please call home,” New Hampshire Union Leader, 17 April 2005. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” Union Leader, 16 May 1990. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” Union Leader, 16 May 1990. ↩︎
- Tom Fahey, “Disappearance of Girl, 14, Baffles Police, Worried Mom,” Union Leader, 7 July 1980. ↩︎
- Shawne K. Wickham, “Tales of alcohol, porn and shadowy figures,” New Hampshire Union Leader, 17 April 2005. ↩︎
- Shawne K. Wickham, “Mom’s plea: Laureen, please call home,” New Hampshire Union Leader, 17 April 2005. ↩︎
- Shawne K. Wickham, “Tales of alcohol, porn and shadowy figures,” New Hampshire Union Leader, 17 April 2005. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” Union Leader, 16 May 1990. ↩︎
- Tom Fahey, “Police Baffled Over Disappearance,” Union Leader, 8 July 1980. ↩︎
- Press accounts from 1980 put the time at around 11:45 PM; articles from 1990 shift it to 12:30 AM. ↩︎
- Shawne K. Wickham, “Tales of alcohol, porn and shadowy figures,” New Hampshire Union Leader, 17 April 2005. ↩︎
- More recent accounts say 1:15 AM. ↩︎
- Frank Donovan, “Mother’s Hopes Renewed for Finding Her Daughter, Missing Since April,” Union Leader, 14 December 1980. ↩︎
- Tom Fahey, “Disappearance of Girl, 14, Baffles Police, Worried Mom,” Union Leader, 7 July 1980. ↩︎
- Tom Fahey, “Police Baffled Over Disappearance,” Union Leader, 8 July 1980. ↩︎
- The poster thought Laureen was 13, but she had turned 14 earlier that month. ↩︎
- Pat Grossmith, “40 years after disappearance, family holds out hope for Laureen: ‘In my heart I want to believe she’s alive…’,” Manchester Ink Link, 27 April 2020. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” Union Leader, 16 May 1990. ↩︎
- Frank Donovan, “Mother’s Hopes Renewed for Finding Her Daughter, Missing Since April 26,” Union Leader, 14 December 1980. ↩︎
- The Charley Project, “Laureen Ann Rahn,” 12 October 2004. ↩︎
- Shawne K. Wickham, “Mom’s plea: Laureen, please call home,” New Hampshire Union Leader, 17 April 2005. ↩︎
- Anita D. Timrots and Michael R. Rand, “Violent Crime by Strangers and Nonstrangers,” US Department of Justice/Bureau of Justice Statistics, January 1987. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” New Hampshire Union Leader, 16 May 1990. ↩︎
- Anita D. Timrots and Michael R. Rand, “Violent Crime by Strangers and Nonstrangers,” US Department of Justice/Bureau of Justice Statistics, January 1987. ↩︎
- Caveat: This is not a representative sample of all homicides. ↩︎
- Caveat: This was a study of adult homicide victims generally; its purpose was not to address adolescent female disappearances. ↩︎
- Caveat: The study focused on cases where disposal was established. ↩︎
- Parameters: “A nonrandom national sample of 840 closed, fully adjudicated state DNA local homicide cases contributed by law enforcement agencies for research purposes. Inclusion criteria consisted of cases where evidence of body disposal existed, the murder method differed from the disposal method (e.g., arson), and where only one offender and one victim were involved, resulting in 119 cases for analysis. The authors had access tot he entire case files, which included police reports; medical examiner, autopsy, and hospital reports; statements from witnesses and offenders; crime scene photos; maps; and forensic evidence and reports.” Population: “Males comprised most offenders (92 percent), and the average age was 32 years old. Perpetrators tended to be white (74 percent), followed by African-American (14 percent), individuals. Regarding the victim-offender relationship, cases involving strangers (30 percent); friends or acquaintances (29 percent); spouses, partners, or exes (25 percent); and other family members (15 percent.)” ↩︎
- The study does not specify the operational criteria used to classify victim-offender relationships (i.e., a formal definition of “stranger.” ↩︎
- Definition: not concealed (the body left completely exposed) ↩︎
- Valeria Flores, et al, “Body Disposal in Homicide,” Featured articles, FBI.gov, 8 April 2021. ↩︎
- Valeria Flores, et al, “Body Disposal in Homicide,” Featured articles, FBI.gov, 8 April 2021. ↩︎
- Christopher Sheehan, “What Ever Happened to Laureen?” New Hampshire Union Leader, 16 May 1990. ↩︎