32-Year-Old Murder of Mary Pierce Solved by DNA

For more than two decades, the green smock with the 7-Eleven logo lay in a box inside the Greeley Police Department evidence room. It was one of the remaining pieces of a puzzle that had haunted the town for all those years. Little did cops know that one day the smock would help them solve the murder of Mary Elizabeth Pierce.

Pierce, 22, had recently graduated from the University of Northern Colorado. She had joined the U. S. Navy and would have been inducted within a few weeks.

On the evening of August 25, 1977, a customer entered the 7-Eleven Store at 11th Avenue and 9th Street. Finding no one there, she called police. Investigators contacted the store’s manager and Pierce was identified as the missing clerk.

Even though a witness reported seeing a suspicious man loitering near the telephone outside the store, investigators assumed that Pierce had left on her own. Maybe she decided to abandon ship and meet up with a boyfriend, they reasoned. Or maybe she hated her job. The cops were wrong.

Four days later, Pierce’s body was found in a cornfield a few miles outside of Greeley. She’d been sexually assaulted and stabbed numerous times. Just another in a string of abductions and murders of female convenience store workers across the country.

When she was found, Pierce was still wearing her 7-Eleven smock. Now the green was splashed with red, causing police to revise their original “runaway” theory.

Two convenient suspects lived nearby. Brothers Juan and Jesus Bautista had served hard time in Utah for a similar crime. Their alibis were shaky, and police honed in on the pair. Cops wouldn’t know it for years, but again they were wrong.

As time ticked away, detectives continued to investigate the crime. In a sure sign of desperation, they hired a psychic. Three men were involved, the seer said. One man alone committed the murder, but look for three. Police already had two suspects--now they wondered who the third man might be.

In 1981, the Bautista brothers were charged with Mary Pierce’s murder. At the time, their residence was a Texas prison. Seven years later, the two were brought back to Greeley to face trial. But even though the prosecutor was convinced that they were the killers, he had no real evidence. As that fact became evident, the brothers were quietly released and remanded back to the Lone Star State to complete their sentences.

The years continued to creep along like a slow-moving stream. But the world was changing. Science had dropped a gift into the lap of law enforcement: DNA. A nearly fool-proof way to identify killers and exonerate the wrongly accused.

At some point during those years, the Mary Pierce case was removed from the Greeley Police Department and placed in the hands of the Weld County Sheriff’s Office.

In 2003, sheriff’s investigator Jan Lemay dug into the evidence box and pulled out Pierce’s smock. The specialist packed off the blood-stained vest to the Colorado Bureau of Investigation for testing. Sure enough, several splotches of blood were identified as belonging to someone other than Pierce. Detectives raced to obtain a DNA sample from the Bautistas, who were still being housed by the Texas Department of Corrections. But there was no match.

Someone else had committed the murder.

A glass slide containing semen from Mary Pierce’s body was found later and also submitted to CBI. It was identified as coming from the same person whose blood was found on the victim’s smock. Cops entered the unidentified DNA into a nationwide database and waited.

In 2009, thirty-two years after the murder of Mary Pierce, a cold hit shocked investigators. The DNA of long-time criminal Marcello Maldonado-Perez matched that found on Pierce’s smock and the semen recovered from her body. Maldonado-Perez had been released in 2008 after serving a long prison sentence in Texas. While there, his DNA had been entered into the FBI’s database. (In addition to the DNA, investigators discovered a fingerprint from Maldonado-Perez on a soda can that had been found at the store.)

As is so often the case, little is known about Mary Pierce. In the criminal justice system, the victim is almost always short-changed. As the case rocks along, we’ll hear more than we ever want to know about Maldonado-Perez. It’s doubtful that true justice will ever be served since only one inmate has been executed by the state since 1976 and Coloradans seem reluctant to pull the plug on any of the three prisoners currently on death row.

Mary Pierce deserves better.