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Murder of Martha Morrison

SOLVED1974Dole Valley, near Vancouver, Washington3 SOURCESUPDATED JUL 2026
Illustrative

Martha Marie Morrison was a 17-year-old resident of Portland, Oregon, who disappeared under unclear circumstances on September 1, 1974. She had grown up largely in foster care in Lane County, Oregon, attended Roosevelt High School in Portland and the Corvallis Farm School, and later participated in the Job Corps program in Arizona. She had a documented history of drug use and of running away from both biological and foster homes. Shortly before she went missing, she had visited family in Eugene with a man with whom she shared an apartment; the couple reportedly quarreled before she disappeared.

On October 12, 1974, human remains belonging to two women were discovered in Dole Valley near Vancouver, Washington. One set of remains was quickly identified through dental records as 18-year-old Carol Platt Valenzuela, who had been reported missing in early August 1974 after failing to return from a hitchhiking trip. The second set of remains could not be identified at the time despite forensic facial reconstructions, nationwide examination, and public appeals. Investigators noted the remains had likely been in the location for at least two weeks, and decomposition and animal activity complicated efforts to determine time or cause of death.

The case remained unresolved for decades. A labeling error discovered in 2011 revealed that Morrison's skull and other bones had been mistakenly stored under Valenzuela's name, contributing to the prolonged delay in identification. DNA comparisons using samples from Morrison's sister and half-brother, and eventually an exhumation of her father's remains funded by the National Center for Missing & Exploited Children, produced a near-certain match. In July 2015, the previously unidentified remains were confirmed to be those of Martha Morrison.

Following identification, investigators continued pursuing leads, and at various points serial killers Ted Bundy and Randall Woodfield were considered persons of interest in the deaths of Morrison and Valenzuela. Attention eventually focused on Warren Leslie Forrest, who had a lengthy history of violence and was already incarcerated for the 1974 murder of Krista Kay Blake; he had been arrested on October 2, 1974, ten days before the Dole Valley remains were found. In August 2017, DNA testing matched a bloodstain on an air pistol owned by Forrest to Morrison. Officials stated this evidence also implicated him in Valenzuela's death, given that the two victims were found together. Forrest was formally charged with Morrison's murder in 2020 and was found guilty of first-degree murder on February 1, 2023. He has also been named as a suspect in other unresolved disappearances from the 1970s.

Key facts

Victims
Carol Platt Valenzuela, Martha Marie Morrison
Date
1974
Location
Dole Valley, near Vancouver, Washington
Case status
solved

Case timeline

  1. 1957

    Martha Marie Morrison is born.

  2. 1974-07

    Krista Kay Blake is murdered; Warren Leslie Forrest is later linked to this crime.

  3. 1974-08-02

    Carol Platt Valenzuela goes missing after hitchhiking to Vancouver, Washington.

  4. 1974-08-04

    Valenzuela is reported missing by her husband.

  5. 1974-09-01

    Martha Morrison disappears after visiting family in Eugene, Oregon, with a man she lived with.

  6. 1974-10-02

    Warren Leslie Forrest is arrested.

  7. 1974-10-12

    Human remains of two women are discovered in Dole Valley near Vancouver, Washington; one is identified as Carol Platt Valenzuela.

  8. 1974-10-25

    Valenzuela's husband, previously arrested, is released after passing a polygraph test.

  9. 2011

    A labeling error is discovered showing Morrison's remains had been mistakenly stored under Valenzuela's name.

  10. 2012

    A DNA profile is developed for the then-unidentified remains.

  11. 2015-07

    The unidentified remains are confirmed via DNA testing to be those of Martha Morrison.

  12. 2016-03

    Police publicly appeal for help identifying Morrison's boyfriend at the time of her disappearance, described as not a suspect.

  13. 2017-08

    A bloodstain on an air pistol owned by Warren Forrest is matched via DNA to Morrison.

  14. 2020

    Warren Leslie Forrest is charged with Morrison's murder.

  15. 2023-02-01

    Warren Leslie Forrest is found guilty of first-degree murder for Morrison's death.

Best coverage

No approved coverage links are attached yet.

People

  • Carol Platt Valenzuela

    VICTIM

    18-year-old victim found alongside Morrison's remains in Dole Valley in 1974; identified via dental records shortly after discovery.

  • Martha Marie Morrison

    VICTIM

    17-year-old victim who disappeared in September 1974; her remains went unidentified for over 40 years before DNA testing confirmed her identity in 2015.

  • Nikki Costa

    LAW ENFORCEMENT

    Investigator who worked on the identification of Morrison's remains and discussed the case in interviews.

  • Warren Leslie Forrest

    CONVICTED

    Charged in 2020 with Morrison's murder after DNA on a bloodstained pistol matched her; found guilty of first-degree murder on February 1, 2023.

Roles reflect public records and court outcomes at the time of writing — supporting citations are on file under Sources.

Places

Dole Valley, near Vancouver, Washington

45.6387, -122.6615

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Common questions

What happened to the victim?
Martha Morrison, a 17-year-old from Portland, Oregon, disappeared in September 1974; her remains, found alongside those of Carol Platt Valenzuela near Vancouver, Washington, went unidentified for over 40 years until DNA testing confirmed her identity in 2015. Warren Leslie Forrest was later charged and, in February 2023, convicted of her murder.
Where did the murder happen?
Dole Valley, near Vancouver, Washington.
Who was convicted?
Warren Leslie Forrest (Charged in 2020 with Morrison's murder after DNA on a bloodstained pistol matched her; found guilty of first-degree murder on February 1, 2023.).
What is the current status of the case?
Status: solved.
More cases in Washington

Sources

  1. ENCYCLOPEDICMurder of Martha MorrisonWikipedia · 2026-07-07
  2. OFFICIAL / AGENCYContemporaneous coverage — eugene-or.goveugene-or.gov · 2026-07-07
  3. PRESSContemporaneous coverage — CBS NewsCBS News · 2026-07-07

Record history

First published
JUL 07, 2026