Prosecutors are in the Victorian County Court appealing the decision to allow convicted paramedic basher James Haberfield to avoid jail.

The then 21-year-old attacked his victim after he fled a hospital following a four-day bender at the Rainbow Serpent music festival.

He was on a cocktail of drugs including ice, MDMA, ketamine and LSD at the time, the court was told.

Prosecutors believe Haberfield should already be behind bars due to mandatory sentencing laws aimed at people who attack emergency workers - but the laws also allow for "special reasons" attackers can avoid prison.

Magistrate Simon Zebrowski decided in August not to send Haberfield to jail because of his age, pre-existing autism spectrum disorder and increased risk of suicide in custody.

Paramedic Monica, who didn't want her surname used, told the court she suffered flashbacks.

"I feel like I'm constantly being choked and suffocating," she said on Tuesday.

She was often triggered into panic attacks and suffered ongoing "distressing flashbacks" where she tries to escape the ambulance.

Monica has not been able to return to work as a paramedic due to her psychological and physical injuries.

Haberfield's family took him to hospital after Rainbow Serpent but he fled and walked into a Coburg home, terrifying the residents.

When paramedics arrived, Haberfield punched Monica's face, put her in a headlock, and squeezed and pinned her to the back door of the ambulance.

He pleaded guilty to recklessly causing injury to an emergency worker and assaulting an emergency worker and was freed.

But prosecutors argued it was not open to Mr Zebrowski to impose any sentence other than a jail term as required by the legislation.

Judge Michael Tinney told the court he had been up until midnight looking at the relevant laws.

The new law "significantly fetters" his sentencing discretion, he said.

Haberfield's lawyer argued his client's impaired mental functioning was caused by recently diagnosed schizophrenia and not just his drug use.

Forensic psychiatrist Andrew Carroll told the court Haberfield had schizophrenia and was "acutely psychotic" during the attack.

Taking the drugs together with his undiagnosed illness was like "pouring petrol" on a fire, he said.

"The illicit substances acted as a potent fuel which severely exacerbated his mental state," Dr Carroll told the court.

But the psychiatrist said if Haberfield didn't take the cocktail of drugs his "severely acute disturbance" in January would not have happened.

Prosecutors said they received "absolutely no notice" about the schizophrenia diagnosis and wanted their own medical expert.

"There needs to be a really strong message that any assault of a paramedic or an emergency worker doing their job can't be tolerated," Victorian Ambulance Union secretary Danny Hill said outside court.

The appeal has been adjourned until December.

Australian Associated Press