A cold case is an unsolved crime that is not the subject of a current criminal investigation, but for which new information could emerge.
Characteristics
Violent or major crime
Typically, cold cases are
Violent crime and other major
felony crimes, such as
murder and
rape, which—unlike unsolved minor crimes—are generally not subject to a statute of limitations. Sometimes disappearances can also be considered cold cases if the victim has not been seen or heard from for some time, such as the case of
Natalee Holloway or the Beaumont children.
Solve rate
The rate of cold cases being solved is slowly declining; soon less than 30% will be solved per year.
Suspect identification
In the search for suspects, some police organizations have created websites featuring cold cases. For example, the Texas Rangers have established a website
in the hopes that it shall elicit new information and investigative leads.
Tunnel vision
Sometimes, a viable suspect has been overlooked or simply ignored due to then-flimsy circumstantial evidence, the presence of a likelier suspect (who is later proven to be innocent), or a tendency of investigators to zero in on someone else to the exclusion of other possibilities (which goes back to the likelier suspect angle)—known as "tunnel vision".
Improvements in forensics
With the advent of and improvements to
DNA testing/
DNA profiling and other
forensics technology, many cold cases are being re-opened and
.
departments are opening cold case units whose job is to re-examine cold case files. DNA evidence helps in such cases but as in the case of fingerprints, it is of no value unless there is evidence on file to compare it to. However, to combat that issue, the FBI is switching from using the Integrated Automated Fingerprint Identification System (IAFIS) to using a newer technology called the Next Generation Identification (NGI). Other improvements in forensics lie in fields such as:
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Digital forensics, one application of which is to Data recovery.
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Ballistics analysis which involves the evaluation of ammunition and firearms to determine which weapon might have been used in a crime.
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Forensic anthropology which analyzes skeletal remains to determine their cause of death or any other relevant information.
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Mobile forensics and social media which, since their creation, have had increased involvement in any police case, cold or not.
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Forensic psychology which can be used to analyze crime scenes and identify suspect profiles.
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Facial recognition which has been used to identify suspects based on their facial features.
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Artificial intelligence (AI) which is used in all of the above systems to help analyze data and information from crime scenes.
Famous criminal examples
The identity of Jack the Ripper is a notorious example of an outstanding cold case, with numerous suggestions as to the identity of the
serial killer. Similarly, the
Zodiac Killer has been studied extensively for almost 50 years, with numerous suspects discussed and debated. The perpetrators of the Wall Street bombing of 1920 have never been positively identified, though the
, a group of
Italians anarchists, are widely believed to have planned the explosion. The
Reichstag fire Reichstag building in 1933 remains controversial and although Marinus van der Lubbe was tried, convicted and executed for
arson, it is possible that the Reichstag fire was perpetrated by the
to enhance their power and destroy democracy in Germany.
Examples of criminal cold cases that ended in conviction
{| class="wikitable sortable"
|-
! scope="col" | Victim(s)
! scope="col" | Convicted
! scope="col" | Location
! scope="col" | Crime date
! scope="col" | Conviction date
! scope="col" | Description
|-
| Victims of Nazis' Neuengamme Concentration Camp (sub-camp in Meppen, Germany)
| Friedrich Karl Berger
| Meppen, Germany
| to March 1945
|
|
In a deportation case tried in 2020 in U.S. Immigration Court in Memphis, Tennessee, US (therefore not strictly a criminal prosecution), Friedrich Karl Berger was adjudged complicit in Nazi crimes of persecution committed while serving as an armed guard for the SS in Meppen, Germany, at a sub-camp of the Neuengamme concentration camp during World War II. This decision, reported in a March 5, 2020, United States Department of Justice press release,
|-
|
Harold Blauer
| rowspan="2"|The Central Intelligence Agency
| rowspan="2"|New York City, New York, US
|
|
|
Retired tennis player who was unwittingly injected with 3,4-Methylenedioxyamphetamine (MDA) after checking himself in to the New York Psychiatric Institute for depression. The experiment was part of the CIA's secret Brainwashing program, MKULTRA, and Blauer's medical records were altered to hide the real cause of his death. MKULTRA was revealed to the public in 1975, and Blauer's estate was awarded $700,000 in damages in 1987.
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|
Frank Olson
|
|
|
A CIA bacteriologist and biological warfare expert who was unwittingly dosed with LSD by his supervisor. Nine days later, Olson had a nervous breakdown and jumped from his 13th-story room at Hotel Pennsylvania. Olson's family agreed to withdraw a wrongful death lawsuit against the agency in exchange for an out-of-court settlement of $750,000 and apologies from President Gerald Ford and CIA director William Colby. Olson's children ordered a new autopsy in 1994 and tried to reopen the case as murder in 1996 and 2012, but both requests were denied because of the previous deal.
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| Richard Phillips, Milton Curtis
|
Gerald Mason
| El Segundo, California, US
|
|
|
Two police officers were shot when they pulled over a car for running a red light. Mason was arrested 45 years later after a computerized fingerprint database identified him as the purchaser of the murder weapon. At the time, he had just raped a 15-year-old girl at gunpoint at a local lovers' lane, and he killed the officers to avoid prosecution for the crime. Mason's back still bore the scar left by a bullet fired by the officers as he fled.
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|
Irene Garza
| John Feit
| McAllen, Texas, US
|
|
|
A 26-year-old beauty queen who disappeared when she went to church for confession and was later found raped and murdered in a canal. Feit, a 27-year-old priest at the church who later pled no contest to raping a parishioner, and left the priesthood in the 1970s, was a suspect since the beginning, but little investigation was made due to the opposition of long-time district attorney Rene Guerra (1980–2014).
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| John Orner
| Edward Freiburger
| Columbia, South Carolina, US
|
|
|
A 60-year-old cab driver who was robbed and murdered on the job with a .32 H&R pistol. Freiburger, then 19 and a soldier stationed at nearby Fort Jackson, became a suspect when it was discovered that he purchased the same weapon at a local pawnshop only hours before Orner received his last dispatch call, after which he went AWOL. Freiburger was stopped by Tennessee State Police a month later and found with the gun in his possession, but ballistics tests were inconclusive and he was never charged. In 2002, a private firearms examiner working for the South Carolina Law Enforcement Division cleaned up the slugs and matched the bullets to the gun.
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| Malika Maria de Fernandez
| Peter Reyn-Bardt
|
Wilmslow,
England, UK
|
|
|
Reyn-Bardt, De Fernandez's estranged husband, made a detailed confession about how he had murdered, dismembered and disposed of her body in the bog behind his home after peat cutters found human remains there, 22 years later. Although Carbon 14 testing later showed the remains to be thousands of years old, Reyn-Bardt's confession was considered enough evidence to convict him of the murder of his wife, whose body was never found.
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| rowspan="3"|Addie Mae Collins, Cynthia Wesley, Carole Robertson, Carol Denise McNair (plus 22 injured)
| Robert Edward Chambliss
| rowspan="3"|Birmingham, Alabama, US
| rowspan="3"|
|
| rowspan="3"|
Victims of the 16th Street Baptist Church bombing. Although the FBI had identified Chambliss, Blanton, Cherry and a fourth Klansman, Herman Frank Cash, as the perpetrators already in 1965, no arrests were made for political reasons, and the case was shelved in 1968. Cash died in 1994 without being prosecuted.
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| Thomas Edwin Blanton Jr.
|
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| Bobby Frank Cherry
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|-
| James Keuler
| Samuel Evans
|
Seattle, Washington, US
|
|
|
Evans, already incarcerated for other crimes, entered an Alford plea after DNA linked him to Keuler's crime scene.
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| Helen Betty Osborne
| Dwayne Archie Johnston
|
The Pas,
Manitoba, Canada
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|
|
A Cree people Aboriginal woman abducted while she was walking home at 2:30 pm and subsequently beaten, raped and stabbed over 50 times. Although four Caucasian race men were implicated in the murder, only Johnston was convicted for it after 16 years, and the case was officially closed on February 12, 1999. The government of Manitoba officially apologized for its poor handling of the case on July 14, 2000.
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| Jackson and Daisy Schley
| Samuel Evans
| Seattle, Washington, US
|
|
|
A couple attacked during a home invasion. Jackson was murdered and Daisy was abducted and raped. Evans entered another Alford Plea for the murder after his DNA was matched to semen recovered from Daisy's clothing. Daisy died of unrelated causes in 2007, before Evans was identified.
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|
Steven Stayner
|
Kenneth Parnell
| Merced, California, US
|
|
|
A seven-year-old boy kidnapped and held in captivity for eight years by Parnell, a pedophile. After Stayner hit puberty, Parnell lost interest in him and kidnapped five-year-old Timmy White from Ukiah, California as his replacement. However, Stayner and White escaped on March 1, 1980, while Parnell was at work, leading to his identification and arrest.
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| Joseph, Julie, Joseph Jr. and Josephine Otero
| rowspan="2"|
Dennis Rader
| rowspan="2"|Wichita, Kansas, US
|
| rowspan="2"|
| rowspan="2"|
A family victim of "BTK", a serial killer who would invade homes and kill women after stalking them for long periods; other members became unintended victims when they returned home earlier than expected. BTK would later write taunting letters to the media and police about his crimes. Rader's arrest was made possible by metadata found in a floppy disk he sent to police and a partial DNA match to his daughter. Neither technology existed at the time he committed the murders.
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| Kathryn Bright
|
|-
| Lizbeth Wilson
| John Henry Horton
|
Prairie Village,
Kansas, US
|
|
|
A 13-year-old girl last seen running across the field of Shawnee Mission East High School by her brother, who was racing ahead of her. Her remains were found in an empty field six months later. Horton became a suspect because he was the only adult working on the school grounds at the time, and the investigation revealed that he had taken a suspicious break and also tried previously to lure other girls into the school. A duffel bag and a bottle of chloroform was found in his car, which Horton claimed using to "get high", but this was deemed circumstantial. In 2002, investigators interviewed an overlooked 15-year-old girl at the time of the murder who had been given chloroform by Horton and was sexually molested while she was unconscious. However, the Kansas Supreme Court overturned Horton's conviction in 2005 on the basis that the "prior bad act" had not been placed on the public record and the testimony should not have been allowed. Leave to re-try and re-file the case was granted, and this time the same evidence and the testimony of two fellow inmates was enough to declare him guilty.
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| Katherine and Sheila Lyon
| Lloyd Lee Welch
| Washington, D.C., US
|
|
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Two sisters aged 10 and 12 who disappeared during a trip to a shopping mall. For decades, the police centered their efforts in locating a 50 to 60 years old man who was seen playing a tape recorder with children in different malls. However, in 2013 the attention shifted to Welch, by then a convicted and incarcerated child molester. Welch, who was 18 in 1975, strongly resembled another man seen stalking the girls by one of their friends, and it was found that in 1975 Welch himself went to the police, claiming that he had seen the older man abducting the girls. After a cousin of Welch confessed to helping him burning two suspicious in his property of Thaxton, Virginia in 1975, the police searched the place and found items that had belonged to the girls. While no trace of their bodies was found, Welch pleaded guilty to both counts of abduction and murder.
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| rowspan="2"|Myrna Opsahl
|
Emily Harris and William Harris, Kathleen Ann Soliah, Michael Bortin
| rowspan="2"|Carmichael, California, US
| rowspan="2"|
|
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A 42-year-old customer killed during the robbery of the Crocker National Bank by the Symbionese Liberation Army. The case was revived only in 1999, after Soliah (indicted for the attempted bombing of two LAPD patrol cars in August 1975) was arrested in Minnesota, thanks to a tip from a neighbor who had watched her case featured in America's Most Wanted.
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|
James Kilgore
|
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Arrested on November 8, 2002, in South Africa, where he was living under an alias, and extradited to the United States. He was the last SLA member to be apprehended and convicted.
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| Martha Moxley
| Michael Skakel
| Greenwich, Connecticut, US
|
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A 15-year-old girl last seen talking to Skakel's brother, Thomas, at a party, and who was bludgeoned and stabbed with a golf club that was traced back to the Skakel home. Over the years, suspicions switched from Thomas to Michael, who was an alcoholic and peeping tom at the time of the murder (when he was also 15) and who was said to have bragged about getting away with murder due to his family's connection to the Kennedy family. Skakel was convicted of the murder in 2002, and again on retrial, in 2016.
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| Claude Snelling
|Joseph James DeAngelo
| Visalia, California, US
|
|
|
Claude Snelling, a 45-year-old journalism professor, was fatally shot when he intervened in the attempted kidnapping of his 16-year-old daughter by the prolific, unidentified burglar known as the Visalia Ransacker; The Ransacker escaped and vanished afterward. In 2018, police announced that the Ransacker was also the unidentified serial killer known as the Original Night Stalker, and that his real identity was DeAngelo, who was identified as the Stalker by a DNA match. DeAngelo was a police officer in nearby Exeter during the Ransacker's spree. DeAngelo was charged with Snelling's murder because of undisclosed, non-genetic evidence. DeAngelo plead guilty to Claude Snellings murder along with 12 others and was sentenced to life imprisonment without the possibility of parole
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| Carol Hutto
| James B. Kuenn
| Largo, Florida, US
|
|
|
A 16-year-old girl whose body was found in a lake near an abandoned house. She was last seen alive the night before when she received a call. Suspicion fell on her 17-year-old half-brother Jerry Irwin, a known juvenile delinquent who had stayed out all night and whose route home took him past the house and lake.[ Tampa Bay: A Cloud of Suspicion Lifts ] However, the real murderer was Hutto's boyfriend, James B. Kuenn, who later joined the US Navy and served in a submarine. In 1998, Kuenn confessed to NCIS agents that he had killed Hutto and disposed of her body after she refused to have sex with him.
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| Shirley Vian
| Dennis Rader
| Wichita, Kansas, US
|
|
|
See above.
|-
| Susan Clarke
| Ralph Andrews
| Skokie, Illinois, US
|
|
|
Clarke disappeared from a babysitting job in Lincolnwood, and her body was found in a vegetable garden two days later. She had been strangled, stabbed and mutilated. A man named Ralph Andrews was suspected early on, but not charged due to a lack of evidence. Years later, after he was convicted in an unrelated 1991 murder, he was charged and eventually pleaded guilty to the Clarke murder, receiving a life sentence.
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| Nancy Fox
| Dennis Rader
| Wichita, Kansas, US
|
|
|
See above.
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| Brian and Katie Maggiore
| Joseph James DeAngelo
| Rancho Cordova, California, US
|
|
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A young couple chased and fatally shot while walking their dog at night. The murders were attributed to the unidentified East Area Rapist, who committed over 50 home invasions and rapes around the time in Northern California, after pre-tied shoelaces with his signature diamond-type knot were found at the crime scene. The EAR was discovered to be the Original Night Stalker after DNA from both sprees was matched in 2001, and in turn, identified as DeAngelo through family DNA in 2018.
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| Deana Lynne Bowdoin
|
Clarence Dixon
| Tempe, Arizona, US
|
|
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A 21-year-old woman who was strangled and stabbed to death in her apartment. In 2001, DNA profiling linked Dixon to the crime, a former neighbor of Bowdoin's, who was serving a life sentence for a 1986 sexual-assault conviction. Dixon was formally sentenced to death for the murder in January 2008 and was executed in May 2022.
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| Melvin "Ricky" Pittman, Ernest Taylor, Alvin Turner, Randy Johnson, Michael McDowell
| Philander Hampton
| Newark, New Jersey, US
|
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Five African-American teenagers who disappeared at once from Newark's Clinton Avenue. In 2008, while being interrogated for an unrelated case, Hampton confessed to having helped his cousin, local contractor Lee Anthony Evans, in luring the victims to an empty house with the promise of work, then locking them in a room and setting the house ablaze. Hampton led investigators to the place of the fire but no human remains were found. In spite of this, Hampton pleaded guilty and was convicted of five counts of murder, while Evans, who claimed innocence, was acquitted.
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| Etan Patz
| Pedro Hernandez
| New York City, New York, US
|
|
|
A 6-year-old boy who disappeared on his way to a school stop; his disappearance helped launch the child abduction and he was the first child with a photo on a milk carton. For decades, suspicion was cast on a convicted child molester, Jose Antonio Ramos. However, Hernandez's brother-in-law identified him as the real perpetrator in 2012, claiming that he had confessed publicly at his church in the 1980s and that his guilt was an open secret in his family. Hernandez confessed again after his arrest, but doubts about his mental health delayed a guilty verdict until 2017.
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| Floralba Sánchez
| Pedro López
| El Espinal, Tolima, Colombia
|
|
|
The only identified victim of López, one of the most prolific serial killers of all time, in his native Colombia. López was tried after he completed his controversial 16-year-long sentence in Ecuador and was deported to his home country.[Cruz Niño, Esteban (2014) Los monstruos en Colombia sí existen. Penguin Random House Grupo Editorial Colombia, 264 pages]
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| Robert Offerman and Debra Manning
| Joseph James DeAngelo
| Goleta, California, US
|
|
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The two first victims of the Original Night Stalker in his Southern California spree. DeAngelo was charged with their murders.
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| Roger Wheeler
|
Johnny Martorano,
Steve Flemmi
| Tulsa, Oklahoma, US
|
|
|
The owner of World Jai Alai, murdered in his car by members of the Winter Hill Gang after he discovered that they were stealing funds from his corporation. Whitey Bulger (a fugitive since 1999) and H. Paul Rico, who died before trial, were also indicted.
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| Green River Killer victims
|
Gary Ridgway
| Near Seattle and Tacoma, Washington, US
| – March 5, 1990
|
|
48 prostitutes and runaways raped and strangled after being picked up along Pacific Highway South. Ridgway was identified in 2001 after a DNA test was made on samples collected from him already in 1987. Ridgway also killed a 49th woman in 1998, 38-year-old Patricia Yellowrobe.
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| Kalinka Bamberski
| Dieter Krombach
|
Lindau,
Bavaria, Germany
|
|
|
A French 14-year-old girl who died in the home of her German doctor stepfather (Krombach) after being injected with a cobalt-iron solution. Because German authorities declined to prosecute Krombach in spite of his testimony being inconsistent about the purpose of the injection and with the autopsy report, Bamberski's biological father, André, lobbied for Krombach to be prosecuted in France. Krombach was tried in absentia in 1995 and found guilty, but the verdict was annulled by the European Court of Human Rights in 2001. In 2009, Bamberski had Krombach abducted from his home and delivered to a French police station in Alsace, where he was arrested. Krombach was tried again and sentenced to 15 years in prison, while Bamberski received a one-year suspended sentence for his abduction in 2014. Since 1997, several German women have come forward claiming that Krombach drugged and raped them as teenagers.
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| rowspan="2"|Dos Erres massacre
| Manuel Pop, Reyes Collin Gualip, Daniel Martínez Hernández, Carlos Carías
| rowspan="2"|La Libertad, El Petén, Guatemala
| rowspan="2"|
|
| rowspan="2"|
Over 200 unarmed Maya people murdered in a punitive expedition of the Guatemalan Army Kaibiles during the presidency of Efraín Ríos Montt, mostly by bludgeoning. Each convict was sentenced to 6,060 years in prison for the crimes.
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| Pedro Pimentel Ríos
|
|-
| Jeanine Nicarico
|
Brian Dugan
| Naperville, Illinois, US
|
|
|
A ten-year-old girl kidnapped from her home by a burglar and subsequently raped and murdered. Two men, Alejandro Hernandez and Rolando Cruz, were convicted in several trials before they were respectively acquitted in 1995, and by the Governor in 2002. Dugan, who pleaded guilty to the crime in 2009, had already confessed to it in 1985.
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| Elaine Graham
| Edmond Jay Marr
|
Los Angeles, California, US
|
|
