On day two of the Renisha McBride shooting trial, Theodore Wafer testified that he didn't know his gun was armed when he fatally shot the 19-year-old victim on his porch.

On Nov. 2, 2013, the teenager crashed into a parked car in Detroit, Michigan after a night of drinking alcohol and smoking marijuana. She wandered around for hours before she ended up in the suburban neighborhood of Dearborn Heights and knocked on Wafer's door to seek help around 4:30 a.m.

Prosecutors say that's when Wafer opened his door and shot the unarmed African American teen in the head. However, his defense team claims that he feared for his life and shot her in self-defense. The 55-year-old defendant faces up to life in prison if convicted on charges of second-degree murder, manslaughter and felony use of a firearm, reports HLN-TV.

On Thursday, prosecutors played audio of the conversation Wafer had with police officers who responded to the fatal shooting.

"What happened here?" Sgt. Rory McManmon asked Wafer on the recording, according to the Associated Press.

"A consistent knocking on the door, and I'm trying to look through the windows and the door. It's banging somewhere else so I open up the door, kind of like who is this? And the gun discharged," Wafer said.

Wafer went on to say that he was not aware that his shotgun was loaded when he reached for the weapon.

"I didn't know there was a round in there," Wafer told McManmon. "I don't get it. Who's knocking on your door at 4:30 in the morning? Bang, bang, bang -- somebody wanting in."

A witness named Paris Pace also gave testimony about Renisha's car accident, telling jurors that the teen was "babbling" and seemed "real out of it."

In addition, officer Mark Parrinello testified that he removed maggots from McBride's clothes at the Dearborn Heights Police Department evidence room days after she was shot, reports MLive.com.

During opening statements, Wafer's defense attorney told jurors he was awaken by repeated loud bangs on his front and side doors, which led him to believe that multiple people were outside of his home. He then grabbed his shotgun after he heard metal breaking on his screen door and opened his door because he didn't know what to do, said his attorney on Wednesday.

However, prosecutors claim that Wafer's "actions that night were unnecessary, unjustified and unreasonable," said Assistant Wayne County Prosecutor Danielle Hagaman-Clark.