Peninsula Woman Pleads Not Guilty To Beating Neighbor To Death With Baseball Bat

A woman who police said admitted to beating her neighbor to death with a baseball bat in San Mateo earlier this month pleaded not guilty to murder Wednesday afternoon, San Mateo County District Attorney Steve Wagstaffe said.

Brenda Martinez, 40, was arrested on July 4 after police said she walked into the police station at about 8:30 p.m. and said she had killed her neighbor, 66-year-old Ellen Mackay.

Officers responded to the neighbor’s home in the first block of North Claremont Street and found her dead from head trauma from a baseball bat, according to police.

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Prosecutors said Martinez and Mackay got into an argument in Mackay’s apartment.

Martinez was enraged, got a baseball bat and allegedly hit Mackay numerous times in the head.

She started to flee but then decided to turn herself in instead, prosecutors said. Martinez is next scheduled to appear in court on Aug. 24 to set a preliminary hearing date.

--Bay City News/File photo