The trial of a Massachusetts man charged with killing the mother of his four children as well as a longtime friend in Maine is winding down. Closing statements in the trial of Joel Hayden of New Bedford, Mass. are scheduled for Monday in Portland. The 31-year-old Hayden has pleaded not guilty to killing his girlfriend, 27-year-old Renee Sandora, and his childhood friend, 28-year-old Trevor Mills, of New Bedford, at Sandora’s home in New Gloucester in July 2011. Evidence presented at trial included the 911 call in which Sandora can be heard saying “my boyfriend just shot me,” and testimony from the couple’s 8-year-old son, who said he saw his father shoot his mother. Hayden’s attorneys told jurors that no gun was ever found and DNA evidence points to another possible killer.