Scott Michael Greene pleads not guilty in police ambush killings

The Urbandale man accused of ambushing and killing two police officers has pleaded not guilty to the two first-degree murder charges filed against him.

Scott Michael Greene is charged in the Nov. 2 shooting deaths of Urbandale Police Officer Justin Martin and Des Moines Police Sgt. Anthony "Tony" Beminio, who were shot 20 minutes apart while each sat in his patrol car. Prosecutors have accused Greene, 46, of shooting both men with a high-powered rifle before turning himself in hours later. 

A court-appointed attorney representing Greene filed the written plea Wednesday. Greene signed the form himself and checked a box demanding a speedy trial, putting the case on track to go to trial beginning on Feb. 13. The trial date could ultimately be continued if Greene waives his speedy trial rights at a later date, which defendants regularly do to give attorneys more time to prepare.

Police and prosecutors have not publicly commented on what allegedly motivated Greene. But reviews of court records and interviews have found that he had a history of volatile and racially charged encounters with police and Urbandale school officials. Just hours before the shooting Greene had been ordered by a judge to move out of his mother's house after she claimed he'd become violent.

Court and police records also indicate that Greene has struggled with mental health issues.

Greene would face two life-in-prison sentences if convicted of the charges. He remains in the Polk County Jail.

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