PORTLAND – William Hanaman, who is charged with murdering his girlfriend last year, is expected to testify today in his own defense.

His trial opened Tuesday in Cumberland County Superior Court. The prosecution is expected to call its last few witnesses this morning.

Hanaman, 52, is charged with killing Marion Shea at his apartment on Ocean Avenue on Nov. 10, 2009.

Police say Hanaman stabbed the 47-year-old mother of five, then tried to kill himself by overdosing on prescription medication. Acting on a phone call from Hanaman’s sister, police entered the apartment on the morning of Nov. 11 and found the pair lying on a bedroom floor. Hanaman was rushed to the hospital for treatment; Shea was already dead.

Hanaman had been charged with domestic violence assault against Shea about a month before the killing, and he was ordered not to have any contact with her.

Hanaman’s lawyer, Robert Levine, says his client acted in self-defense, and he killed Shea because she came at him with a knife.