A FATHER has been sentenced to life behind bars for fatally stabbing a young man in a “senseless act of violence” after a brief argument over a lighter.

Travis Raymond Robinson, 38, was in the CBD with his son in January when he came across 20-year-old Piripi Phillips and his friends near the Wesley Church on William Street.

Mr Robinson chatted with the group for a short time before getting into an argument with Mr Phillips over a lighter.

Mr Phillips punched Robinson twice and started walking away but he had only made it a few steps when the older man stabbed him twice with a knife.

Passerbys, including two registered nurses, tried in vain to help the heavily bleeding victim as Robinson fled on foot.

Supreme Court Justice Joseph McGrath jailed Robinson for life with a minimum of 15 years today for his “grossly disproportionate” crime.

He described the fight in the lead-up to the stabbing as relatively minor and said Robinson staggered but did not fall when he was hit.

“The deceased had struck you but was walking away,” Justice McGrath said.

“It was a senseless act of violence. It was an immediate response by you after being struck by the deceased.

“The offending that you have done has taken the life of a young man.”

Justice McGrath accepted Robinson did not intend to kill Mr Phillips and was remorseful for what he had done.

But he said the thing that struck him was that Robinson’s now 11-year-old son was with him when he murdered the victim.

Robinson produced a knife and a cut throat razor when he was being chased by a police officer in an arcade after the stabbing.

The stabbing was captured on CCTV footage, which was shown to Robinson as he sat in Hakea Prison after the murder.

Defence lawyer Seamus Rafferty said it was “just so sad” that a person had lost their life over something as inconsequential as a lighter.

“This was, and not in the legal sense, just a moment of insanity in the circumstances that it was an overreaction to a wrong that was done to him,” he said.

“There is an understanding that those close to the deceased may not take much from that.

“It’s hoped they will accept that deep remorse shown by my client.”

The court was told Robinson started using cannabis at age 13 and later started abusing prescription drugs and taking amphetamines, hallucinogens and opiates.

In a victim impact statement, Mr Phillips’ sister described the despair Robinson had caused her family.

She said each day was filled with sadness and anxiety as she thought about the senseless loss of her much-loved brother.

Outside court, Mr Phillips’ uncle Paul said his nephew was loved and respected by his family and the community.

Robinson’s sentence was backdated to January.