Man jailed over bizarre SA carjacking

A man high on a synthetic drug, who went on a bizarre carjacking rampage and bit a police officer, has been jailed for just over four years.

Aaron Sumner Wilson, 46, was under the influence of mephedrone, when he dragged a woman from her car at Murray Bridge, east of Adelaide, in August last year and went on to crash into other cars and a power pole before being arrested.

District Court Judge Paul Muscat said Wilson's behaviour could only be described as bizarre and highlighted just how irrational people could become after taking amphetamine-based drugs.

At different times during Wilson's drug-induced psychosis witnesses described him as being totally off his face with a psychotic look in his eyes.

Judge Muscat said Wilson was rambling about people trying to kill him, pumping him full of drugs and there being a bomb inside him, while the police who tried to arrest him said he was "fighting much like a wild animal".

The judge said Wilson was extremely fortunate not to have seriously injured or killed an innocent member of the public.

"Let this be a warning to those who use illicit drugs and become psychotic," Judge Muscat said in sentencing on Wednesday.

"People need to realise they will be held accountable for their drug-induced behaviour in the same way as if they were stone cold sober."

Wilson had earlier pleaded guilty to a string of charges including theft, illegally interfering with a car and aggravated assault.

His offending began when he deliberately rode his bike towards a four-wheel-drive with the woman behind the wheel fearing he was trying to commit suicide.

He crashed into the car but jumped up, dragged the woman out and sped off, with the vehicle becoming airborne at one stage before the rampage ended with him smashing into the power pole.

Wilson then tried to steal the car of a witness who came to his aid before sinking his teeth into the arm of a police officer called to the scene.

Judge Muscat said Wilson's behaviour was disgraceful but stemmed from three years of heavy drug use, including mephedrone, known on the street as meow meow.

He said that drug use had been sparked by the impact of mental health issues and family tragedies, including the deaths of his father and brother and more recently the loss of his former partner's baby.

The judge imposed a total head sentence of four years and two months with a non-parole period of 20 months.