In testimony, laid out in a 140-page report, Tammy's daughter said there was a road rage incident with another vehicle that led to a collision and then a shootout.
But, police maintain there was never a crash.
The testimony has three different witnesses, and there are three different descriptions of the suspect vehicle.
Tammy's daughter said it was a silver, four-door vehicle with no tinted windows. Brandon, Tammy's son, remembers it as a Grey, four-door vehicle with tinted windows. The police officer told the court that Nowsch said he got into a cream-colored vehicle.
The officer added that Nowsch said he knew Tammy and had been to her house before for dinner.
He testified that Nowsch believed the victim's vehicle was after him, and he was scared for his family's safety, claiming there had been people after him, threatening to skin his cat, mother and sister.
Daughter Krystal told the grand jury she knew Nowsch but didn't believe it was him in the suspect vehicle the night of the shooting.
Son Brandon went on the record saying he had a cellphone, but was too much in shock to call police after the first round of gunfire erupted.
Nowsch has pleaded not guilty to all charges against him, including murder. His trial will begin on May 26.