Opposition Leader Jeremy Hanson will seek feedback on an exposure draft with new types of offences and sentences related to unprovoked, serious criminal assaults known as "coward's punch" attacks. Releasing the plan on Friday, he said anyone found guilty of serious one-punch attacks causing death should face up to 25 years in jail.

The plan would see changes to the Crimes Act, including the creation of a new aggravated offence to deal with one-punch attacks and tougher penalties for grievous bodily harm, assault and affray. Mr Hanson said he'd take the issue to this year's election if the government or Greens Justice Minister Shane Rattenbury didn't support the plan.

Attorney-General Simon Corbell said the opposition's plan would in fact reduce the maximum penalty for instances where someone is killed, from a life sentence to 25 years. Mr Rattenbury, who has supported previous law and order plans from the opposition, also sounded a sceptical response on Friday.

"These changes are simply a con job on the community," Mr Corbell said.

"When you look at the other offences that are being proposed, they are an increase of only two years on top the maximum penalties that are currently available.

"We know that increasing penalties does not prevent violence.People don't think about the penalty they're going to get when they're drunk and punch somebody."

Labelling the plan as "grandstanding" by the Liberals, he said the government would instead focus on education and harm prevention to try and stop drunken violence outside popular Canberra nightspots.

Last year Mr Corbell ruled out introducing new offences, or mandatory minimum jail sentences, for one-punch attacks and other forms of alcohol-related violence.

Mr Rattenbury said he was yet to see the exposure draft, but expressed similar sentiments to Mr Corbell.

"I will be having a look at it and will be interested to see how [Mr Hanson] sees this as different from what's already available in the criminal law space.

"I think the more significant area we need to be looking at is how do we tackle alcohol-related issues at their root. A one-punch attack usually comes as a consequence of excessive alcohol or drug consumption," Mr Rattenbury said.

ACT Victims of Crime Commissioner John Hinchey commended the opposition for raising the debate over harsher penalties but called for a broader approach to violence.

"I think the opposition has correctly judged that the community has reached a level of complete intolerance to the level of violence we have seen with these coward's punches," he said.

"In addition to any legislative reform that is to be considered in detail is the need for the community to also shift the culture around violence, the idea of what it is to be male, and a regulatory response to our use of alcohol in and around licensed premises."

Mr Hinchey also welcomed the opportunity for one-punch perpetrators to come face-to-face with their victims when the ACT's restorative justice program expands in coming months.

He said the ACT also needed to be sensible about the availability of alcohol in the city.

"We need to ensure there is a sense of safety at night in these areas and that is certainly not the case under the current regulatory framework.

"Evidence suggests restrictions on alcohol sales, restricting density of licensed venues and making a high-profile presence of police have been shown to reduce alcohol-related violence.

"I think it's time the ACT progressed its liquor reforms which have been on the table for the past year. We need to begin treating this issue urgently before someone else is injured or killed, which is what could have happened to the young man on New Year's [Eve]."