A group of lawyers is trying to stop the Conservative government from deleting a massive backlog of 280,000 immigration applications, saying the move is unfair because people have been waiting to come to Canada for years.

The government announced its decision to wipe out the application backlog in its March budget, saying it is a necessary part of modernizing the country's immigration system.

The omnibus bill C-38, which the Conservatives hope to pass this summer, would see the elimination of applications under the Federal Skilled Worker Program created before 2008.

Lorne Waldman, an immigration lawyer based in Toronto, says that breaks a promise to applicants who followed all the necessary steps to come to Canada.

"They've been waiting in the queue for years and years, and now [Immigration Minister] Jason Kenney is saying, 'Yeah we told you to wait in the queue, we told you that was the right way but that's too bad. Now we've changed our mind and there's no longer going to be a queue for you.'

"I think that's immoral," he said.

Along with several other lawyers, Waldman is seeking class-action certification for a lawsuit, which now has about 40 litigants from China and Hong Kong, that would challenge the decision to eliminate the backlog and force the government to process applications.

He says he will also seek an injunction when bill C-38 passes in order to prevent the law from being applied.

The government has said it would refund the fees from the 280,000 applications and officials with Kenney's office say they are confident the bill will withstand a legal challenge.

The government has also said applicants are welcome to reapply under any other immigration stream, including a revamped foreign skilled workers category that prioritizes language and job skills to help fill shortages in Canada's workforce.

The Harper government is making other changes to Canada's refugee system through a separate omnibus bill, C-31. Amendments to that legislation are up for debate in the House of Commons Thursday at report stage.

This lawsuit is aimed at C-38, the budget implementation bill.