Prosecutors and defense agree, Walnut Creek homeless man was legally insane at time of stepping stone murder
Mark Banducci, 64, pleaded no contest to bludgeoning 52-year-old Steven Keeler to death, with the addendum that he will be sent to a state mental hospital in lieu of prison.
MARTINEZ — In a plea deal with Contra Costa prosecutors, a 64-year-old man has admitted to bludgeoning a man to death with a stepping stone, but will be sent to a state mental hospital in lieu of prison.
Mark Banducci, of Walnut Creek, pleaded no contest to murder in the death of 52-year-old Steven Keeler, but with the agreement that he was legally insane at the time of the homicide. As is required by state law in these types of agreements, a judge convicted Banducci of murder then immediately ruled he was not guilty by reason of insanity.
Banducci was arrested and charged in June 2021 with beating Keeler to death with a stepping stone. Police said at the time both men were homeless, but did not say how they knew one another, nor did they publicly release the suspected motive. He was originally charged with lying in wait and ambushing Keeler, which would have made him eligible for life in prison without the possibility of parole.
People found not guilty by reason of insanity can be held in a mental hospital for the duration of what their prison sentence would have been, which in this case is life with a chance for parole. It is also possible he could be released if deemed to have recovered from mental illness.
Neither prosecutors nor Banducci’s attorney commented on the case’s outcome.