A Quebec man who has been convicted on numerous drunk-driving charges will face 20 years in prison if a judge makes legal history and labels him a dangerous offender, according to a legal analyst.

Last December, Roger Walsh pleaded guilty to an impaired-driving charge -- his 19th -- after he struck and killed 47-year-old Anee Khudaverdian in October.

The wheelchair-bound woman was out with her dog on what was her 47th birthday when she was struck by Walsh's minivan and thrown into a ditch.

Walsh was arrested nearly 10 kilometres away when he crashed into a ditch. His blood alcohol level was more than double the legal limit of .08.

On Wednesday, a judge will decide if Walsh should be labelled a dangerous offender, status usually given to the most hardened criminals, such as murderers and serial rapists.

The designation carries an automatic prison sentence of 20 years, followed by 10 years of close surveillance.

If a dangerous offender breaches the conditions of his release, he will return to jail indefinitely.

"It will be historic. It will be the first of its kind," CTV legal analyst Steven Skurka told Canada AM on Tuesday. "Does it mean that prosecutors will pounce on this immediately for every repeat offender seeking the dangerous offender application? Absolutely not. But I think it will slowly create a change where not just for murder cases, not just for the worst sexual assault cases such as repeat rapists, where there will be dangerous offender applications."

The Conservative government introduced the legislation last year as part of its Tackling Violent Crime Act.

Under previous guidelines, only the most violent criminals would be labelled dangerous offenders and would receive indefinite prison sentences.

Two attempts under the new rules to have repeat drunk drivers labelled dangerous offenders, one in Ontario and one in Alberta, have failed.

But Mr. Walsh's criminal history is unprecedented when it comes to considering the dangerous offender designation.

Walsh has 114 criminal convictions on his record, including 19 drinking and driving offences. His other convictions are for offences that range from bail and parole violations and mischief, to theft and aggravated assault.

Khudaverdian's sister, Clara Khudaverdian, has been advocating for tougher laws since her sister died.

"If they don't hand it down (in this case), we're in trouble -- an impaired driver will never be given a sentence like this again," Khudaverdian told The Canadian Press.

"If people know this (dangerous offender status) is a possibility if you re-offend, they may think twice."

Walsh's lawyer, Jacques Vinet, is calling for a 10-year prison sentence.

According to Skurka, the judge must consider the issue of public safety when making his decision.

"This person is clearly a public security threat. His criminal record is an encyclopedia," Skurka said. "Should this person be allowed back into the community? Certainly not for a very long time. If he doesn't get the dangerous offender tag, the sentence has to start at 15 years. Anything lower than that would be unconscionable."

Skurka also said that Walsh's case begs the question: Why wasn't this man in jail?

"I think it's not good enough to say, 'Let's sentence him, let's put him away for the rest of his life,' because people have died," Skurka said. "There's a tragedy in this case that needs some explanation. There needs to be some accountability. And there may be that there have been serious, egregious errors in the past that have allowed Mr. Walsh to continue as he did."

With files from The Canadian Press