TAMPA, Fla. (WFLA) — Bryan Riley, the Marine accused of killing four members of a Lakeland family pleaded not guilty in a Polk County court today.

Previous reporting by the Associated Press said Riley’s defense was considering an insanity plea, but the document submitted in Polk County Circuit Court does not mention such a defense.

For the deaths of the four members of the Lakeland family and the attempted murder of a fifth family member, Riley currently faces 18 counts for the shooting, which left an infant dead and a child injured, in addition to the deaths of three adults.

Riley is a former sharpshooter who served in Iraq and Afghanistan from 2008 to 2010 before his honorable discharge, according to Polk County Sheriff Grady Judd. He then reportedly spent three years in the reserve and had no criminal history.

According to the sheriff, Riley’s mental health was a factor in the shooting, and Riley’s girlfriend said he was having mental health issues, but had not been violent.

The document says that Riley reserves the right to file motions in his own defense challenging the legality and sufficiency of the grand jury indictment he faces.

By entering a plea of not guilty, the court document says that Riley and his defense request a trial by jury.

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