Violent criminals will no longer be able to argue they were drunk or affected by drugs to avoid jail time under tough new laws promised by the Victorian Government.

What the changes mean: Assaulting paramedics, police, firefighters or prison staff to be classified as Category 1 offence

Assaulting paramedics, police, firefighters or prison staff to be classified as Category 1 offence Effects of drugs and alcohol no longer any excuse to avoid prison for a number of offences

Effects of drugs and alcohol no longer any excuse to avoid prison for a number of offences Courts to give "less weight" to a defendant's life circumstances when sentencing

Courts to give "less weight" to a defendant's life circumstances when sentencing "Psychosocial immaturity" for 18 to 21-year-olds also no longer a reason to avoid prison time

The Government has been under pressure after two women last week avoided a prison sentence after being found guilty of assaulting paramedics — an offence that prescribes mandatory jail time.

On appeal, the women — who had a history of abuse and mental illness — were able to avoid prison because of "special reasons" provisions that provide for exceptions to custodial sentences.

Premier Daniel Andrews this morning announced that such provisions applying to all statutory minimum prison sentences in Victoria would be overhauled and restricted. Drug or alcohol-induced impairment will no longer be allowed as an excuse.

"[We are] sending the message to the Victorian community that if you think you can go and be drunk and behave this way and somehow be treated differently and get off — no, you will go to jail,'' Mr Andrews said.

"If you are on ice or some other drug and you think that is somehow going to get you out of being held to account for injuring an emergency service worker — no, that won't get you out either."

Tough upbringing no excuse, Premier says

Joined by the leaders of the police and ambulance associations, Mr Andrews also announced that ''psychosocial immaturity'' would also be removed as a "special reason" for offenders aged between 18- 21.

The changes will also force the courts to give significantly less weight to the life circumstances of the offender when sentencing.

People suffering mental health issues and psychosis will still be able to plead not guilty on those grounds, Mr Andrews said.

Paramedics have been campaigning for the reforms. ( ABC News: Simon Galletta )

The Premier said the changes, to be introduced to Parliament in mid-June, meant more Victorians would go to prison.

''We will do everything we can to protect those who protect us. This sends the strongest possible message — if you attack and injure an emergency worker, you will go to jail,'' Mr Andrews said.

A paramedic in Victoria is attacked, on average, every 50 hours.

The law change follows Cabinet's decision on Monday to upgrade the classification of any attack on an emergency worker to a Category 1 offence — the same level as murder and rape — which requires a custodial sentence for anyone found guilty.

The Government will also grant extra powers to the Director of Public Prosecutions to appeal against exceptions to prison time given to offenders under the special reasons provisions.

Lawyers question mandatory sentencing

The Law Institute of Victoria is calling for an "urgent" meeting with the Attorney-General, saying in a statement that "magistrates and judges must have discretion when it comes to sentencing".

Mandatory minimum sentences for assaulting emergency service workers were introduced by the Napthine Coalition government in 2014 and the Labor Government has attacked the design of those laws as a reason for the current problems.

The ambulance and police unions have welcomed the changes. ( Twitter: Danny Hill )

The Chief Judge of the County Court, Peter Kidd, defended the discretion judges currently have to impose their own forms of punishment.

"The sentence is tailored to the particular circumstances of the case," Judge Kidd told ABC Radio Melbourne.

"When substantial punishment is called for, it's imposed. At the other end of the spectrum there'll be other cases, because of special circumstances, individual circumstances that warrant some mercy.

"Mandatory sentencing is the opposite of individualised justice. Mandatory sentencing says one size does fit all … and the fact is one size doesn't always fit all."

He also criticised sections of the media for the way it reported last week's court case, saying it went beyond fair criticism.

Chief Judge Peter Kidd said some media coverage of the original case had been denigrating. ( Office of Public Prosecutions )

"Some of the press coverage in relation to the judge involved in the emergency workers case has been, unfortunately, quite denigrating," Judge Kidd said.

"One cartoon … in a pictorial metaphor suggested Her Honour was responsible for the physical injury.

"A lot of the press suggested her honour was just on a frolic.

"Here's a judge who's simply applying the law as best she can, working hard to do so."

Questioned about the decision to give less weight to offenders' life experiences, such as being victims of abuse, Mr Andrews said people deserved justice.

''I'm all for providing support to people who need that support. I don't however accept that everyone who has had a difficult background behaves in this way, I don't accept that,'' he said.

Defence lawyers argue mandatory sentencing is a ''blunt instrument'' that does nothing to prevent crime.

Melbourne lawyer Rob Stary said mandatory sentencing was ineffective. ( ABC News )

''The statistics show that mandatory sentencing does not deter crime,'' prominent defence lawyer Rob Stary said.

''It only serves two purposes and that is retribution and vengeance.''

Mr Stary, who has defended terrorism suspects and underworld figures, said the courts should have the discretion to determine when people are sent to prison, taking into consideration the gravity of the offence and the circumstances of the offender.

"You shouldn't sentence someone who's 18 years old and a first offender and suffers a form of illness in the same way as a 35-year-old person that's been in and out of jail their whole life,'' he said.

The Opposition, which is planning to introduce a private members bill on Tuesday to also narrow the special reasons provision, supports removing drugs and alcohol-induced impairment and psychosocial immaturity as special reasons.

But Opposition Leader Matthew Guy said he had concerns that the restrictions on courts giving weight to a defendant's life circumstances was too loose.

''If you allow the courts to interpret what is 'less weight', we all know what the courts will interpret that to be, there will be no change at all. The Government needs to provide definition as to what less weight [is],'' Mr Guy said.