Elizabeth Roach can’t be certain how her friend, University of New Hampshire football player Todd Walker, was shot and killed while they were out together in Boulder, Colo., last March.

What she can be certain of is that, with her back turned to the altercation between Walker and his alleged killer Kevin McGregor, the gun in McGregor’s hand went off, the Daily Camera reports. The bullet that was fired claimed Walker’s life.

Now ten months later, McGregor is on trial and Roach has to relive the entire horrid experience.

“Roach wept as she described the confrontation with the gunman that ended with the death of her friend Walker,” the Camera reports.

The article goes on to report that the two sides have portrayed the March 18 incident in very different lights. Only one piece of information is unquestionable fact, according to the Camera: Two rounds were fired, one into the air and one into Walker.

The prosecution is claiming that after a brief exchange between Roach and McGregor, Walker stepped in to defend his friend.

“Leave her alone. We don’t have any money,” Walker said, according to Roach’s testimony.

“[He was] glued to the ground,” she continued.

Roach reportedly decided to walk away from the altercation, hoping Walker would join her. After walking away and with her back turned, however, the fatal shot was fired.

Boulder County District Attorney Stan Garnett showed jurors a Facebook post McGregor made from [his workplace] a few hours after the shooting that said, ‘haha [expletive] son, what now?'” the Daily Camera reports. “[A]nd a private message sent to a friend via Facebook the next morning that said, “might as well call me a gangsta, [expletive] went off tonight, n I ain’t about to type it. I’ll tell you when I cruise down if I’m still free.'”

The defense reportedly calls the shooting an accident. Public defender John Gifford argued that McGregor whistled at Roach, and Walker stepped in. Intimidated, McGregor pulled out his gun. When Walker tried to grab it from him, it went off in the struggle.

“This started with a whistle and an argument about that whistle,” the Camera quoted Gifford as saying. “He did not commit the crime of first-degree murder. He did not commit the crime of felony murder. He did not commit the crime of aggravated robbery.”

Only McGregor knows what truly happened that night. The jury is expected to make its decision next week.