Explosive testimony was delivered Wednesday in the trial of a man accused of driving drunk and killing a 12-year-old Boy Scout.

Authorities say Thomas Murphy, 60, was driving drunk in September last year when he slammed his Mercedes into 12-year-old Andrew McMorris and a group of Boy Scouts on a hike.

Robert Dougherty, an assistant scoutmaster, testified about what happened that day and described the moments when the crash happened. Dougherty told the jury that he never saw any of the Scouts walking in the roadway from where he was in the back. He said when he went to see what happened after the crash, he heard Murphy say "Oh...(Expletive)...I'm in trouble."

Also taking the stand was Murphy's longtime friend and golf buddy Steven Meola. He told the jury that he saw Murphy have several vodka drinks that day. He also testified that Murphy only played six holes of golf and was having trouble walking and slurring his words. When it was time to leave the golf course, Meola told the jury he said, "I told him I should drive home...cause I didn't think he was fit to drive."

"My heart breaks every day over the immeasurable loss of my child," says Alissa McMorris. "And today it breaks even more with these poor boys and men having to go through and relive this nightmare over and over again."

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Defense attorney Stephen Politi argued that his client wasn't drunk and that this was a tragic accident caused by a group of poorly supervised Scouts who wandered into the roadway.

"I don't believe they were hit in the shoulder," says Politi. "I believe the testimony from Mr. Dougherty was pretty clear. The boys were allowed to freely flow, change positions. The adults changed positions as the conversations flowed. And the original order of the hike is not something that was kept."

Murphy has pleaded not guilty to a 16-count indictment that includes aggravated vehicular homicide.