COTTONWOOD HEIGHTS — A former Salt Lake County deputy district attorney faces more trouble after he was arrested over the weekend.
A warrant was issued for Matthew George Nielsen charging him with witness tampering, child abuse and domestic violence.
Nielsen was arrested at his house about 1 a.m. Saturday. Cottonwood Heights Police Sgt. Mark Askerlund said detectives could see someone was inside the house when they arrived with the warrant, but no one answered the door when police announced their presence.
"He turned off all the lights and decided not to come out," he said.
Investigators entered the house and called out to Nielsen, but he still wouldn't answer. It wasn't until officers announced they were about to send a K-9 inside that he came out from hiding in a closet, Askerlund said.
"He was very subdued, very lethargic," Askerlund said.
The arrest warrant was for an incident that allegedly occurred Sept. 3. Police say Nielsen's 16-year-old daughter and 12-year-old son were awakened by the sound of someone screaming, according to court documents. Police say they went to the garage and found their father assaulting his girlfriend.
When the daughter told her father to stop, he allegedly kicked her. After threatening to call police, Nielsen chased his children to their rooms, where he grabbed his daughter "and began punching her in the chest and stomach" before telling her, "If you call the police, I'll kill you," the charges state.
Nielsen also threw his son against the wall and hit him when he tried to help his sister, according to prosecutors.
The children eventually called their mother, Nielsen's ex-wife, to pick them up. As they were leaving, Nielsen threw a bag at his daughter, hitting her in the back, according to the warrant. He also threatened to kill his ex-wife when she arrived, the charges state.
He was charged with witness tampering, a third-degree felony, four counts of child abuse, a class A misdemeanor, threat of domestic violence and two counts of commission of domestic violence in the presence of a child, class B misdemeanors.
The incident came just a month after Nielsen was arrested in a separate case. On Aug. 1, police say the same girlfriend went to Nielsen's house where he punched her and knocked her out, then dragged her into the garage where he poured beer on her, according to court documents.
After later trying to make a run from Nielsen's house, he sprayed her with mace, the charges state. The woman continued running to a neighbor's house for help.
Nielsen was charged in 3rd District Court with class A misdemeanor counts of assault and failing to stop at the command of a law enforcer, and class B misdemeanor counts of criminal mischief and damaging a phone.
Nielsen was with the Salt Lake County District Attorney's Office until 2008 after being the subject of a fraud investigation.