Lawyers for a man charged with killing three Alexandria residents over a 10-year span say their client is innocent and that his mental illness and paranoia made him the target of unfounded suspicions.

At a pretrial hearing Thursday, lawyers for Charles Severance won the right to tell jurors about Severance's mental illness at his upcoming murder trial.

Prosecutors say the former Alexandria resident with a history of erratic behavior shot and killed three city residents in their homes dating back to 2003. Their evidence includes writings by Severance glorifying murder and his failed effort to gain asylum at the Russian embassy when police tried to interview him.

Defense lawyers say schizophrenia is behind Severance's writings and behavior.

Prosecutors say Severance is competent. They opposed allowing testimony about his mental health.