A police officer faces the end of his career after being assaulted while arresting a drunken man north of Brisbane last year, the District Court has been told.

Judge Philip Robin QC said as an unintended consequence of the incident Sen. Const. Mark Zeller had seriously injured his knee while struggling with Brent James Mattingley, 24.

Mattingley pleaded guilty to assaulting a police officer causing him bodily harm on 18 December and to a public nuisance charge and a charge of possession of a knife in a public place.

Crown prosecutor Brendan White said that during the arrest, Mattingley hit Sen. Const. Zeller in the face with his handcuffed hands, cutting him.

He told Judge Robin the cut required stitches, but because of the knee injury Sen. Const. Zeller had been restricted to light duties and was looking to change careers.

He said the cause of the knee injury could not be blamed on Mattingley.

Mr White said on 29 August last year State Parliament had amended the law concerning assaults on police officers in the execution of their duties by doubling the maximum penalty to 14 years imprisonment when the assault caused bodily harm.

Defence counsel Ruth O’Gorman said the assault was more of a “lashing out” than an attack.

She said Mattingley had been addicted to cannabis from a young age and had been drinking heavily at the time of the incident.

She said he regretted his actions and had been seeking help for his cannabis addiction and anxiety disorder at a clinic at Currumbin on the Gold Coast.

Mattingley told Judge Robin: “I’m very sorry for what I have done and I am disgusted in the way I behaved”.

Judge Robin said he accepted that the incident had been a momentary lack of control.

Mattingly was sentenced to 15 months’ imprisonment but granted immediate release on parole. His probation was extended to coincide with his parole period.