Mr Yarl, then 16, was shot after he went to the wrong home as he was picking up his twin brothers from a friend’s house a block away.
His family says he did not have his phone with him.
The teenager was shot in the head and arm outside of Andrew Lester’s home in Kansas City, Missouri.
Mr Lester, a retired aircraft mechanic, was charged with first-degree assault and armed criminal action, but pleaded not guilty.
The 84-year-old’s attorney, Steve Salmon, said his client was acting in self-defence, terrified by the stranger who knocked on his door as he settled into bed for the night.
Mr Lester previously admitted that he shot Mr Yarl through the door without warning because he was “scared to death” that he was about to be robbed by a Black person standing at his door.
Mr Yarl testified at the hearing that he rang the doorbell and waited for someone to answer before reaching out to grab the storm door, assuming his brother’s friend’s parents were there.
He said Mr Lester told him: “Don’t come here ever again,” right before shooting him through the door.
The teenager then scrambled away and tried to seek help. However, according to his aunt Faith Spoonmore, he had to go to three houses before someone finally agreed to help him.
The shot to his head left a bullet embedded in his skull, testified Dr Jo Ling Goh, a pediatric neurosurgeon who treated Mr Yarl. It did not penetrate his brain, however, and he was able to go back to high school. He is now a senior and is making plans to major in engineering in college.
The shooting drew international attention amid claims that Mr Lester received preferential treatment from investigators after he shot Mr Yarl. President Joe Biden and several celebrities issued statements calling for justice, while Mr Yarl’s attorney, Lee Merritt, has called for the shooting to be investigated as a hate crime.
“Unfortunately, race is a major factor in who gets justice and who doesn’t and in cases where there is a white man and a Black child,” Mr Merritt told Good Morning America.
Mr Yarl’s supporters were seen in the courtroom wearing T-shirts reading “Ringing a doorbell is not a crime” which were turned inside out.
Family friend Philip Barrolle said they wore the shirts that way after being told by the court the shirts were a problem. Supporters have worn them in the past, but an order issued on Monday barred “outbreaks, signs, or displays of any kind.”
“It is up to us to have our presence felt,” Mr Barrolle complained afterward.