Testimony began today in the trial of the man accused of strangling his girlfriend to death.

The murder trial of Nixon Bourguignon, 37, got under way in Rockland County Court in New City.

Bourguignon is charged with the strangling death of his girlfriend Shannon Coleman at the apartment they shared in May 2014. In his opening statement, the prosecutor said he would show that Bourguignon murdered Coleman.

The defense contends that Bourguignon was under the influence of the sleep aid Ambien. They do not dispute that Bourguignon strangled the woman.

On the witness stand this morning were two neighbors who testified about noises coming from Coleman and Bourguignon's apartment before calling 911. When police arrived they found Bourguignon, who was a fill-in mail carrier at the White Plains Post Office, was on the outside deck. They say he quickly went inside and turned off the lights.

Once they entered the apartment, police say they found Coleman, 29, dead of asphyxiation in the bedroom. They then found Bourguignon hiding in the closet with wounds to his arms and throat. They say Bourguignon told them he had cut his throat with a knife.

Bourguignon told police after his arrest that Coleman had yelled at him for watching too much SportsCenter. He says he got angry because she was texting a man who is the father of her 10-year-old son. Bourguignon says he was afraid they might be getting back together.

Coleman and Bourguignon had a 7-year-old boy together, who was also living with them. Officials say Coleman's two sons, who were home at the time, were not hurt in the incident.

Bourguignon is charged with second-degree murder. He has been in Rockland County Jail without bail.