A Perth father has broken down in tears after a jury found him not guilty of stabbing a man to death with a screwdriver during a fight in Fremantle.

Key points: Andrew Doan was fishing when he heard a comment he interpreted as racist

Andrew Doan was fishing when he heard a comment he interpreted as racist A verbal fight broke out between him and Charles McCarthy that turned physical

A verbal fight broke out between him and Charles McCarthy that turned physical Mr McCarthy was stabbed in the head with a screwdriver when he rushed at Mr Doan

Andrew Doan, 35, had been fishing with a friend on Riverside Drive in the early hours of Saturday, December 23, 2017.

At the same time, Charles McCarthy was walking from a work Christmas function with his wife and a colleague towards the Tradewinds Hotel.

A verbal fight broke out between the trio and Mr Doan over comments that he interpreted as racist.

Giving evidence during the trial, Mr Doan recalled one of the men in the group calling out to him and his friend as they emerged from the river, asking whether they had caught anything.

After replying that they had not had much luck, Mr Doan — who is of Asian descent — testified he heard one of the men say, "Fisheries are going to get you," a comment he interpreted as racist.

"People stereotype that all Asians catch undersized fish, all Asians eat undersized fish," Mr Doan told the court.

"Here we are just trying to fish in peace and quiet. There was no reason for anyone to abuse us like that."

Charles McCarthy was walking from a work function with his wife when the incident took place. ( Supplied: Facebook )

He said he pursued the group, imploring them to stop walking, and calling them racist — at which point the men in the group became defensive and aggressive towards him.

The argument escalated and Mr Doan told the court he removed a screwdriver, which he had intended to use to catch crabs, from his jumper pocket.

The prosecution argued Mr Doan had been the aggressor in the incident and had intentionally stabbed Mr McCarthy.

McCarthy looked 'demonic': Doan

But Mr Doan testified that the victim rushed at him and he raised his hands to protect his face, causing Mr McCarthy to impale himself on the screwdriver.

"You could see the rage in his eyes," he said.

"It was almost demonic looking, it was really scary."

A jury found Andrew Doan not guilty of both murder and the lesser charge of manslaughter. ( Facebook )

He told the court that despite attempts by the victim's wife to restrain her husband, Mr McCarthy rushed at him and he instinctively raised his hands to cover his face.

"I remember just lifting my arms really quickly. I was bracing for impact."

When asked whether he knew the screwdriver was in his hand at that point, Mr Doan replied, "I forgot about it".

Mr McCarthy sustained a traumatic brain injury and died in hospital the following day.

A Supreme Court jury took less than an hour to find Mr Doan not guilty of both murder and the lesser charge of manslaughter.

He and members of his family wept as the verdict was handed down.

Supporters of Mr McCarthy, who is originally from the Irish city of Cork, were also in the court for the verdict.

Relatives of Mr McCarthy were in court to hear Mr Doan found not guilty of murder. ( ABC News: Charlotte Hamlyn )

Doan thanks supporters

Mr Doan has been in custody since his arrest after the incident. After being released today, broke down in tears as he thanked his family and friends for their support.

"It's really good to be back with everyone, family and friends, I've missed them all so much," he said.

"I can't say how much I love them all, so much, their support the whole time."

He said he was shocked when he heard the not guilty verdict, describing the past 13 and a half months as "a crazy roller coaster."