Trial began Thursday for a man who fell asleep at the wheel of his truck killing a Honolulu police officer near Ko Olina two years ago.
James Dorsey was 20 years old when he made the biggest mistake of his life -- driving while drowsy.
"You'll also hear him say that he was tired, so tired that he was bobbing his head," said Deputy Prosecutor Kristine Yoo.
Dorsey doesn't deny being tired that fateful night on Sept. 13, 2011, and his attorney says he believed he could make it home from Makiki to Maili. He didn't.
Dorsey slammed into Honolulu police officer Eric Fontes along the side of Farrington Highway.
"The sound of impact, like a loud impact. Like a boom," said former Honolulu Police Department officer Thomas Chun-Ming.
Chun-Ming was one of three officers stopped along the highway assisting with a traffic stop. He was narrowly missed being hit.
Officer Herman Scanlan wasn't so lucky. Dorsey's truck hit him too. Scanlan doesn't remember much of that night.
"To me, I felt safer with all these lights, but apparently not that night," said Scanlan.
Prosecutors say Fontes was killed by the impact. The narrow path Dorsey's truck took is nearly impossible to imagine and the defense claims it was certainly not intentional.
"The question you must ask yourselves is whether James should be found criminally liable for the choices he made that day. And the evidence will show he is not," said defense attorney Carmel Kwok.