BINGHAMTON, N.Y. -- Jurors must decide whether the murder of David Sanborn and attempted murder of Jordan Doolittle was justified.

Opening statements in the Nicholas Chappell murder trial took place Monday. Chappell is charged in the murder of 23-year-old Sanborn and the attempted murder of 26-year-old Doolittle.

It happened August 31, 2016 on Mozart Street. Chappell and Doolittle were roommates. Amid a property dispute, Doolittle moved out of their apartment.

The prosecution said, on the day of the shooting, Doolittle and his friend, Sanborn, went to the apartment to pick up Doolittle's belongings. Prosecutors claim Chappell let Doolittle and Sanborn in the apartment building and directed Doolittle upstairs. They said Chappell then aimed a shotgun at Sanborn's head and fired.

Doolittle then charged Chappell as another shot was fired. That shot struck Doolittle in his forearm.

The defense does not deny that Chappell fired the shots; however, they argue the shooting was justified. They claim the incident began as a burglary.

The defense stated that Chappell heard a car outside his apartment, but saw no one. They said Chappell then heard someone using the outside keypad, but when he called out to ask who was there, there was no reply.

The defense went on to say Chappell announced he was armed and, when he saw his door opening and someone's head peek through, he fired the first shot. Chappell said he saw a second person on the steps and after firing again, he was tackled.

The defense said Chappell had been a victim of a robbery in the past and is a non-confrontational person.

Prosecutors say Chappell purchased the shotgun and ammunition in July.

Both Doolittle and Chappell will testify in court.