BATTLEFORD, Sask. -- A key Crown witness in the trial of a Saskatchewan farmer charged with shooting an Indigenous man on his property said he lied to police and the Crown about carrying a gun and breaking into a truck on the day his friend was killed.

Under cross-examination, 18-year-old Cassidy Cross admitted he changed his story the day before he took the witness stand Thursday in the second-degree murder trial of Gerald Stanley.

Scroll down or click here for a recap of courtroom proceedings from CTV reporters

"After the trial started you thought it good to take the Crown and the police officer aside and say actually we did have a gun, it was my gun, we were stealing, we used the gun to try and break into a vehicle?" Defence lawyer Scott Spencer asked. "So that's all stuff you told the police last night after court?"

"I told the Crown," Cross responded. "Because honestly I was scared for myself and I was scared for the people there that they might get into trouble. I know that was wrong but that's just how I was feeling over there."

Cross added that he was willing to face the consequence for the sudden departure from his testimony at an earlier preliminary hearing.

"I was young. I was stupid and I've changed a lot since that happened," Cross replied.

Cross was driving an SUV carrying four friends that entered Stanley's farm on Aug. 9, 2016.

Stanley, 56, has pleaded not guilty to second-degree murder after another man in that vehicle, 22-year-old Colten Boushie, was shot in the back of the head.

Cross testified he had about 30 shots of alcohol and was drunk on the day of the shooting.

Court has already heard that at around the same time of the shooting, RCMP received a report about a suspected theft from a truck at a farm about 15 to 20 kilometres from the Stanley property. A grey SUV with a flat tire, matching the one Cross was driving, was spotted at that scene and police found the broken stock of a gun.

Cross initially told investigators that he and his four friends in the SUV were just checking out the truck, but on the stand, he admitted they were trying to steal and that they had used the gun to break in.

"I lied about me going into that truck," he testified. "My intentions were to go steal."

The SUV then rolled up to the Stanley farm, but Cross said the group was simply looking for help with the tire.

"I wasn't there to steal," he told court.

Stanley's son, Sheldon, has testified he and his dad heard an all-terrain vehicle start and thought it was being stolen. The pair ran toward the SUV and threw a hammer at the windshield as the driver tried to leave the farm.

Cross said he was blinded by glass when the SUV's windshield was smashed. He said he jumped out and ran after the SUV hit another vehicle on the Stanley farm.

"We didn't think about it. We just ran. I was scared out of my mind," he said. "As I was running and got to the approach I heard a ricochet. I heard a bullet right by my right ear."

Sheldon Stanley testified he went in the house to get his truck keys and heard two gunshots. He said he heard a third when he came back out. He testified he saw his father standing beside the SUV looking sick with a gun in his hand saying, "It just went off."

Another passenger in the SUV, Belinda Jackson, testified the group had been drinking the entire day before arriving at the Stanley property. She said her memory of the day was fuzzy but she remembers seeing an older man coming out of a garage while they were still in the vehicle.

"He came out with his own handgun. He came around the car to the passenger side and he shot Colten in the head. I'm not comfortable describing how he shot him," she said.

Jackson said she heard four shots fired and two were at Boushie. Court has already heard that Boushie was shot behind the wheel of the SUV. But Jackson said Boushie was in the passenger seat.

Jackson told court she originally told police she thought Boushie was shot by a woman.

"I wouldn't say I lied to them. I didn't tell them the whole truth," Jackson said. "Everything started coming back to me later when I was on my own.

"Maybe I was just scared. It's understandable. It's not something I see every day, seeing someone get shot. I was confused a lot of the time."

Crown prosecutor Bill Burge warned the jury in his opening statement "there may well be some serious contradictions to what people saw."

Live updates from court in Battleford, Sask.