DETROIT (AP/WWJ) — In a twist, a Detroit-area man is testifying in his own defense at the murder trial where he’s accused of shooting of an unarmed teenager who showed up drunk on his front porch before dawn last November.

Lawyers generally dissuade clients from taking the stand to defend themselves in high-profile cases, but Theodore Wafer plodded ahead Monday.

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He’s charged with second-degree murder in the killing of 19-year-old Renisha McBride. His lawyer called him to testify Monday on what is the seventh day of testimony in his trial.

Wafer says he shot McBride in self-defense, adding when he opened the door the screen dropped, and “the person” came out fast. He raised his gun and shot, he said.

“I knew I had to get my gun, I didn’t know where this was going,” Wafer said. “I thought somebody was coming through that door any time.”

Prosecutors say Wafer didn’t need to open his locked front door and could have called 911 instead of confronting and shooting McBride.

To acquit Wafer, the jury would have to find that he shot McBride because he had a reasonable and honest fear for his life.

WWJ’s Marie Osborne reports that Wafer told the jury he couldn’t find his cell phone the night McBride came to his door, saying he wishes he would have found it. Before the shooting, he said he had three beers at a local bar and was home by 7 p.m.

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Why did he have a shotgun at the ready?

He testified, Osborne said, that he had loaded it about a month before the shooting after a neighbor had a run-in with three men.

He bought it in 2008, saying he’s “not getting any younger,” and “lives alone,” Osborne reported, adding Wafer was very soft spoken on the stand.

Wafer said McBride’s banging on his door made him feel like the floor was “rattling under me.”

Prosecutors presented a video of Wafer being questioned by police just hours after the shooting in which Wafer was sipping coffee, expressionless.

When asked about McBride, Wafer said he thinks about her every day. “This poor girl, she had her life ahead of her,” he said.

So why did he open the door? Wafer said  he didn’t want to “cower in my own home,” adding, “I did not want to be a victim in my own home.”

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