'Yogurt Shop Murders': Austin's unsolved cold case continues to raise questions decades later

More than 30 years after the brutal murder of four teenage girls in an Austin yogurt shop, a crime that stunned the city and remains unsolved, a new HBO Max docuseries is shining fresh light on the cold case.

On Dec. 6, 1991, firefighters responding to a blaze at the I Can't Believe It's Yogurt store made a horrifying discovery: the bodies of Eliza Thomas, 17; sisters Jennifer, 17, and Sarah Harbison, 15; and Sarah's best friend Amy Ayers, 13. 

All had been shot in the head. Authorities believe the girls were bound, some sexually assaulted, and that the fire was intentionally set to destroy evidence.

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The crime shocked Austin, a city that "lost its innocence" that night, a Texas lawmaker said. 

"I remember at the time how shocking it was because I think Austin, at that time, was still a relatively small town in Texas that kind of lost its innocence on that day," Rep. Michael McCaul, R-Texas previously told Fox News. 

McCaul, former Texas deputy attorney general and former federal prosecutor, passed legislation giving the families of cold case victims the opportunity to petition the federal government to reexamine cases older than three years. 

The legislation, known as The Homicide Victim Families' Rights Act, requires the federal government to inform family members of cold case victims of their right to do so, the congressman explained.

"This brutal murder of four teenage girls, and the way it was done … that may happen in other cities, but not Austin. It was very shocking, and part of it is because the families never got a resolution to the case."

The initial investigation led police to 17-year-old Maurice Pierce, who was found carrying a handgun similar in caliber to the murder weapon. Pierce's arrest prompted questioning of three other teens, Michael Scott, Robert Springsteen, and Forrest Wellborn.

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Over the next eight years, three of the young men confessed at different times to involvement in the murders. Scott and Springsteen were convicted in 2001 and 2002. However, their convictions were later overturned due to questionable interrogation methods and a lack of physical evidence, and no DNA matches.

By 2009, both men were released, and all charges were dropped. Pierce and Wellborn were never convicted. No one has ever been held accountable for the murders.

Investigators say more than 1,200 people were considered potential suspects over the years, and false confessions were common. In 1992, a biker gang leader in Mexico was briefly suspected but later cleared after revealing his confession had been extracted through torture.

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The focus eventually returned to the four original suspects, but without physical evidence to tie them to the crime scene, the case unraveled in court.

A 2020 DNA test reportedly linked crime scene evidence to an unknown male, according to the Austin American-Statesman. The FBI is said to have a sample from the same individual, but legal hurdles have so far kept Austin police from accessing it.

Detective Dan Jackson, who took over the case in 2022, told USA Today earlier this year that the fire and firefighting efforts destroyed key evidence, but he remains optimistic.

"If I didn't believe this case could be solved, I wouldn't be doing this," Jackson said. "The technology we have today is far beyond what we had just a few years ago … I truly believe we'll find who did this."

A spokesperson for the Austin Police Department told Fox News Digital that they are unable to comment on the details as the case remains an active and ongoing investigation, adding that there is no additional information available for release.

HBO Max's four-part docuseries The Yogurt Shop Murders, which debuted Aug. 3, revisits the case and shines a spotlight on alleged investigative mistakes. The series features interviews with detectives, victims' family members, and never-before-seen footage from an abandoned documentary, according to Variety.

For many in Austin, and the families of Eliza, Jennifer, Sarah and Amy, the hope is that the renewed attention, combined with advanced forensic tools, will finally bring justice.

"The yogurt shop murders left an undeniable mark on the Austin community. More than 30 years later, we still mourn the loss of those four teenage girls and long for answers about their deaths," Congressman McCaul told Fox News Digital. 

"I'm grateful a light is being shone on the yogurt shop murders again and hope those responsible will ultimately be brought to justice."