SAN JOAQUIN COUNTY, Calif. — True Crime Chronicles is featuring the "Speed Freak Killers'" crime spree on their newest episode. Here is what you need to know about Wesley Shermantine and Loren Herzog, the two men who were responsible for the murders that terrorized San Joaquin County.

The murder spree lasted almost 15 years, beginning in 1984. Shermantine and Herzog were arrested in 1999 after investigators found a victim's blood in Shermantine's car, according to an article by the New York Times.

Shermantine was convicted of four murders: Cyndi Vanderheiden, Chevelle Wheeler and two men who were shot in their car on a stretch of highway in 1984, according to the New York Times.

Vanderheiden was the daughter of the owner of a local bar, the Linden Inn. Shermantine and Herzog were reportedly regulars at that bar, according to the New York Times.

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Herzog was found guilty to three murders in 2001, according to the New York Times, but was paroled in 2010 after an appeals court threw out his conviction. The appeals court said the investigators coerced Herzog's confession.

Herzog may have hanged himself hours after receiving a phone call from Leonard Padilla, a Sacramento area bounty hunter, according to the New York Times. Padilla told Herzog that Shermantine was going to reveal where the bodies were hidden.

Shermantine is on death row at San Quentin Prison. He does not have an execution date because Gov. Gavin Newsom signed an executive order placing a moratorium on the death penalty.

The San Joaquin County Sheriff's Department was accused of refusing to help Hayward Police figure out if the kidnapping of 9-year-old Michael Garecht was linked to the Speed Freak Killers, according to an article by the San Francisco Chronicle.

Sen. Cathleen Galgiani (D-Stockton) accused San Joaquin Sheriff's Department of deleting files of missing persons after learning about a possible location of victims near Linden.

True Crime Chronicles is a weekly true-crime podcast from VAULT Studios and TEGNA, hosted by Will Johnson and Jessica Noll, that takes a look at a new case each week. They take a fresh look and deep dive into a case that one of our TEGNA stations has covered and brought a new perspective, updates and interviews with family, police, the accused and the reporter who covered the story.  

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