Corey Pethybridge, 25, of Sir Neville Howse Place, was stopped about 2.40pm on January 21 and immediately told police he was in possession of a knife that was between the strap of his backpack and his body.

Magistrate David Day raised his criminal history while in court.

"He was a bit a wild child, a wild man too," Mr Day said.

However, Pethybridge said he had since quite using drugs and stopped using cannabis about four months ago.

"I'm trying to change myself," Pethybridge said.

Mr Day convicted him and gave him a 12-month conditional release order.

"It's clear he hasn't committed any further offences since 2016 ... until this year when he was sentenced for driving with an illicit drug in oral fluid," Mr Day said.

"He's demonstrated a capacity to rehabilitate himself."

Pethybridge said he'd just bought the knife and he was advised to carry a receipt when purchasing knives to take home.

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