David Dalrymple

On January 13, 2022, David Allen Dalrymple, 64, was arranged for the February 24, 1982 rape and murder of 9-year-old Daralyn Johnson in Nampa, Idaho. Johnson disappeared while walking to the Lincoln Elementary School. Her remains were found three days later in a drainage ditch near the Snake River. She died by drowning.

Charles Irvin Fain was wrongfully convicted in March of 1984 of the murder and sentenced to death. His hairs were similar in appearance to those found on Johnson’s body, and he lived about a block away from her. Other evidence at his original trial included a shoe print “match” and testimony from jailhouse informants who had received reduced sentences for their testimony – a highly unreliable form of evidence. Fain presented evidence of an alibi, which was corroborated by witness testimony. Semen samples taken from Johnson were destroyed.

Fain spent 18 years in prison. He was exonerated in August of 2001 through DNA testing of pubic hairs found on Johnson’s underwear and sock during her autopsy. The laboratory analysis was performed by noted forensic scientist Greg Hampikian of the Boise State University.

Reports also state that mitochondrial DNA testing on the hairs was performed by innocence attorneys in 1993. It is not known why Fain was not exonerated at that time. Fain only received a certificate of innocence ad compensation in the amount of $1.3 million USD in 2021.

The FIGG investigation was conducted by Barbara Rae-Venter in partnership with the Canyon County Sheriff’s Office. Rae-Venter was joined in the investigation by Stephen Kramer, Melissa Parisot, Monica Czajkowski, and Kirk Campbell.

The case is notable because a forensic STR profile was not able to be developed from the hair, although a SNP profile suitable for FIGG was developed. There is now an Interim Policy (2019) preventing federal agencies from working cases in which the suspect’s DNA cannot be compared with that found at the crime scene using forensic STR DNA typing. That policy was not yet in effect when this early case was investigated, and it is the first of its kind.

Dr. Ed Green of UC Santa Cruz and his laboratory performed the DNA analysis on a hair taken from Johnson’s underwear. Green’s lab has pioneered the typing of rootless hairs. They have published a method, Nguyen et al., whereby genotypes from bone fragments and rootless hairs can be compared with crime scene DNA when STR-typing cannot be done due to the small sample size or degradation.

The method, called IBDGem, compares the SNP profiles from the two samples and provides a likelihood ratio of their relatedness. IBDGem can give probative information on how likely it is that a suspect’s DNA profile is included in that obtained from rootless hair found at a crime scene. It is not known if IBDGem was used to make the final confirmation that Dalrymple’s DNA was included with that found at the crime scene.

IBDGem is important because it enables match probabilities to be calculated and entered into evidence even when a traditional STR profile is not available. In this case, Dalrymple’s STR DNA profile was in CODIS, but this match could not have been made through CODIS since an STR DNA profile of the hair could not be developed.

Dalrymple is facing charges of first-degree murder and rape in the Idaho Third District Court in Canyon County. In August of 2023, the court issued an important ruling on the prosecution’s obligations to disclose information about the use of FIGG to the defence. The court found that the state is required to disclose to the defence all information it has in its possession that led it to accuse the defendant. The state does not have to disclose information not in its possession, including third party genealogical databases.

Dalrymple was living along the route from Johnson’s home to her elementary school at the time of the murder and he has a history of sexual offences. He is currently in the custody of the Idaho Department of Corrections where he is serving a minimum 20-year term for sex offences against a minor under the age of 16, as well as the kidnapping of a separate victim. He was convicted of both crimes in 2004.


Gross, Alexandra. “Charles Fain.” National Registry of Exonerations, June 2012. Last modified January 14, 2022. Accessed December 20, 2023. https://www.law.umich.edu/special/exoneration/Pages/casedetail.aspx?caseid=3209.

Idaho Innocence Project. “Charles Fain: Idaho Death Row Exoneree Who Helped Inspire the Creation of the Idaho Innocence Project.” Idaho Innocence Project, citing Raymond Bonner, “Death Row Inmate is Freed After DNA Test Clears Him.” New York Times, August 24, 2001. Accessed December 20, 2023. https://www.boisestate.edu/innocenceproject/exonerees/.

ISHI. “Debunking Myths Surrounding Law Enforcement’s Use of Forensic Genetic Genealogy.” ISHI Blog, January 12, 2022. https://www.ishinews.com/debunking-myths-surrounding-law-enforcements-use-of-forensic-genetic-genealogy/.

Nguyen, R., Kapp, J. D., Sacco, S., Myers, S.P., and Green, R.E. “A computational approach for positive genetic identification and relatedness from low-coverage shotgun sequencing data.” Journal of Heredity 111 (2023): 504-512. DOI: 10.1093/jhered/esad041.

State of Idaho v. David Allen Dalrymple. Transcript of Proceedings Held on August 11, 2023 Before the Honorable Thomas W. Whitney District Court Judge. In the District Court of the Third Judicial District of the State of Idaho, in and for the County of Canyon.

Stevenson, Ian Max. “Cold Case: Authorities Charge Inmate with 1982 Murder of Tampa Girl.” East Idaho News, January 13, 2022. Accessed December 20, 2023. https://www.eastidahonews.com/2022/01/cold-case-authorities-charge-inmate-with-1982-murder-of-nampa-girl/.

Terhune, Katie, and Tristan Lewis. “Man Charged in 1982 Murder of Tampa 9-Year-Old.” KTVB7 News, January 13, 2022. Accessed December 20, 2023. https://www.ktvb.com/article/news/crime/daralyn-johnson-david-dalrymple-murder-1982/277-8fb25df6-366e-4017-be6b-79f6e9882186.

United States Department of Justice. Interim Policy: Forensic Genetic Genealogical DNA Analysis and Searching. United States Department of Justice. Washington, D.C. Effective 11.01.2019.


First Name David
Last Name Dalrymple
Other Names
Victims 1 (Details)
IGG Started nd
Case Cleared 2022-01-13


Case ID Name Age Case Opened Location Investigating Org Most Serious Charge Disposition Court
2133 Daralyn Johnson 9 1982-02-24 Nampa, ID Canyon CSO First degree murder Case is currently pending before the court Canyon CO DIST CT

Last updated: February 13, 2024

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Case data and narrative licensed under CC BY 4.0: Dowdeswell, Tracey (2023), “Forensic Genetic Genealogy Project v. 2022”, Mendeley Data, V1, doi: 10.17632/jcycgvhm96.1. All other content, including photos, have been added.