Edmonton lawyer Fred Kozak represents the group and expects the paperwork to be filed in court this week. He's not certain it's the first challenge to the law but hasn't heard of any others.
He plans to argue that the law presumes guilt and violates people's rights by suspending their licences indefinitely.
"It punishes people before there's any determination that they've done anything wrong," Kozak said Monday.
"In some cases, it forces innocent people to plead guilty even in circumstances where most people could agree there's no reasonable basis for the charge against them."
Starting last July, people who are pulled over and blow over .08 have their vehicles impounded for three days and lose their licences until their cases are resolved in court.
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Kozak said it can take up to a year for a drunk driving case to get to court in an urban centre, and as much as two years for those living in rural areas without access to public transportation.
"The loss of your licence can essentially mean the loss of your job, the loss of your livelihood, the loss of your ability to support your family."
He said the challenge represents a handful of cases from across Alberta, each with different facts.
"We're using those facts to illustrate how this new regime can be unfair to people."
Other provinces have passed similar laws but they all specify a fixed period of time for licence suspensions, Kozak said.
He said the court challenge will also argue that the Alberta government is stepping into Ottawa's territory. Alberta has no jurisdiction over criminal law, only licensing.
When the law was initially passed, the Criminal Trial Lawyers Association expressed concern. The province said the indefinite suspensions were designed to send a tough message and government lawyers advised it would survive a court challenge.
Kozak said it could take a year before the challenge is heard. In the meantime, perhaps even next month, he plans to ask the court to stay his clients' licence suspensions until the matter can be heard.
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