Man pleads guilty to 9 felonies for killing wife, 2 daughters, and abusing bodies in Miami-Dade

Jury in penalty phase to decide if Alberto Sierra gets death or life imprisonment without the possibility of parole

Miami-Dade corrections has been holding Alberto Sierra since Nov. 20, 2012.

MIAMI-DADE COUNTY, Fla. — A 42-year-old man pleaded guilty to nine felonies on Friday related to the 2012 murders of his 29-year-old wife, his two step-daughters, and the abuse of two of their bodies in Miami-Dade County.

Gladys Machado and her two daughters, 4-year-old Daniela Padron and 8-year-old Julia Padron, died on Nov. 10, 2012, at their home in the area of Northwest 73 Avenue and Fourth Street, according to deputies.

Machado had given a neighbor access to the home, and the neighbor followed a putrid smell to a bedroom closet, found their bodies, and called 911 on Nov. 13, 2012, according to deputies.

Deputies arrested Alberto Sierra, then 28, on Nov. 19, 2012. Detective Rosie Cordero-Stutz, now the Miami-Dade Sheriff, talked to reporters about the case after the arrest.

“He used a plastic bag to asphyxiate Gladys,” Cordero-Stutz said. “And after that, he sexually assaulted her.”

Detectives searched for Machado’s 6-year-old son, who also lived at the home, but wasn’t there on Nov. 13, 2012. They found him safe with his grandmother.

Miami-Dade prosecutors filed the felony case against Sierra on Nov. 20, 2012, and he pleaded not guilty on Nov. 29, 2012.

The nine charges: Three counts of first-degree murder, three counts of kidnapping, two counts of abuse of a dead human body, and armed burglary.

The state is seeking the death penalty. Jury selection in the capital penalty phase is Aug. 17. Miami-Dade County Circuit Judge Marisa Tinkler Mendez has been presiding over the case.

Local 10 News Photojournalist Tim McFarland contributed to this report.

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Andrea Torres

Andrea Torres

The Emmy Award-winning journalist joined the Local 10 News team in 2013. She wrote for the Miami Herald for more than 9 years and won a Green Eyeshade Award.