A car driven into the sea was used "as an instrument of murder", a murder trial has been told.
The prosecutor was giving his closing speech in the trial of a woman accused of murdering her colleague by driving him into a harbour, where he drowned.
Marta Herda of Pairc Na Saile, Emoclew Road, Arklow, Co Wicklow is charged with the murder of 31-year-old Csaba Orsos on March 26, 2013.
The 29-year-old Polish waitress has pleaded not guilty to murdering the Hungarian at South Quay, Arklow.
Brendan Grehan SC, prosecuting, told the Cental Criminal Court that the prosecution's contention was simple and straightforward, that Ms Herda had deliberately driven into the water.
"Whether she did it on the spur of the moment or thought about it beforehand is irrelevant," he said, explaining that the intention for murder could be formed at the time.
"Someone overheating, losing the run of themselves can commit murder," he explained.
He said that the prosecution case relied to a large extent on circumstantial evidence.
"In this case, it's the prosecution's contention that a car driven into the sea was used, in effect, as an instrument of murder," he said.
He said that, as well as having the facts, the jury could draw inferences.
"If you see a door wide open in a house in the early hours of a morning . . . you might well think that person, whenever they went out through the door, must not have intended to go away, but must have intended to come back in," he said.
The court heard that Mr Orsos' front door was found open after the incident.
He said the CCTV evidence showed Ms Herda's car driving from the direction of her home towards the area where Mr Orsos lived around 5.30am that day. It was not in dispute that Ms Herda was the driver and was alone.
He noted that an eyewitness said the woman was on the phone and animated.
He said that critical phone evidence showed that Ms Herda rang the deceased three times that morning.
"She's last on the phone to Csaba Orsos at 5.37," he said.
He noted that a nightwatchmen heard a car driving at speed down the quays around 5.50am.
"He mentioned that a brake-mark, measuring 13 foot 6 inches, was found at the scene.
"It was brought about as the result of a hand brake applied in the car," he noted.
"We don't know who applied the handbrake, but we do know that it, like in most cars, was between the passenger and driver seat."
He noted that the driver's window was the only one down.
He reminded the jury that Ms Herda was found soaking wet in very light clothing on a bitterly cold night when it was snowing.
He also pointed out that Ms Herda was a good swimmer and knew that Csaba Orsos could not swim.
He then moved on to Marta Herda's own words.
"He shouldn't have been there. I drove the car into the water," she told a paramedic that morning.
"He didn't think I'd do it," she told a nurse.
A doctor had asked if she knew what would happen when she went into the water. He said she nodded and said that she knew he couldn't swim.
Mr Greham said that one of the key questions in the case was how Mr Orsos came to be in the car with her.
"There is such a convenient loss of memory as to that critical matter," he said.
"She claimed to the gardai that she can't remember how he came to be in her car or even phoning him, but she can remember everything up to that."
He said the prosecution case was that she acted with deliberate intent when she drove off the pier and asked for a verdict of guilty of murder.
The jury will hear from the defence this morning.