A key witness took the stand Wednesday in Richard McTear's murder trial.

McTear, 25, is charged with first-degree murder, aggravated child abuse and other offenses in the death of Emanuel Murray Jr. The 3-month-old was found dead by the side of Interstate 275 near Fowler Avenue in May 2009.

The child's mother, Jasmine Bedwell, was emotional as soon as she took the stand. She detailed what happened before she said McTear took her baby and killed him.

It’s the second time Bedwell has taken the stand in McTear’s murder trial. The first, she caused a mistrial by saying something in front of the jury she wasn’t supposed to.

This time—she was crying, and careful as she told the jury what happened.

Bedwell said she returned home one night to find her ex-boyfriend, Richard McTear hiding in her home. She said McTear attacked her—then her baby.

“As I was coming down the hallway he came out of the bedroom,” she said. “He was punching me, choking me, scraping the inside of my mouth.”

Bedwell said McTear was furious after he learned she was dating another man.

“Richard McTear went to fridge, got a gallon of water was drinking it, got a soda and opened it. He poured the soda all in my baby’s face,” cried Bedwell.

Bedwell showed jurors how McTear threw her baby’s car seat—with Emmanuel inside. She picked up her baby to escape.

“I got to the door unlocked, he grabbed the baby, threw him to the concrete,” she said.

Bedwell called 911 for help. But by then, she said her baby was gone. That’s when prosecutors say McTear took the baby in the car, drove to I-275, and tossed him out the window, to his death.

Bedwell was in a deputy’s car out looking for McTear when they stumbled upon the crime scene. That’s when she learned what happened to her son.

If McTear is convicted, he could face the death penalty. The trial is expected to take three weeks.