A teenager spun the wheels of his car before driving at speed towards a stationary patrol car, as three gardai attempted to flee for safety, a trial heard.
Seventeen-year-old Jamie McGrenaghan swerved left at the last minute in a bid to escape arrest but struck Garda Robbie McCallion (29) catapulting him through the air "like a rag doll".
Gda McCallion died of his injuries less than two weeks after the incident in Tara Court, Letterkenny, on March 26, 2009.
Mr McGrenaghan, now aged 19, from Grotnatraw, Kerrykeel, Co Donegal, has denied a charge of manslaughter but has admitted a charge of dangerous driving causing death.
It is the prosecution's case that he drove his car towards three gardai as a "form of missile" on the night causing them to run for their lives.
At Letterkenny Circuit Court yesterday evidence was heard of statements he made to gardai in the aftermath of the incident.
He said he could not remember whether he hit "the wall first or the guard" and said he may have hit them both at the same time.
Mr McGrenaghan told gardai he was sorry for what had happened and he hoped the officer recovered quickly.
"I was panicking, drinking and in shock and I didn't know what to do," he told gardai.
Mr McGrenaghan admitted admitted reversing at speed when he saw the gardai and spinning his wheels before driving towards the patrol car. Mr Alex Owen SC, for the prosecution, told the jury that the case was much more serious than a dangerous driving causing death case.
"He was essentially using the car as a form of missile. The garda evidence is that they had to run for their lives," he said.
Mr Denis Vaughan-Buckley SC, for the defence, said the evidence was that Mr McGrenaghan wanted to get away and panicked. He saw a gap that he thought he could fit through and he went for it.
The trial is expected to conclude today.