The Green Party is heading to federal court this week in a last-ditch attempt to get a seat at the leaders' debate.

The party is scheduled to go to court on Tuesday to seek Leader Elizabeth May's inclusion at the televised leaders' debate scheduled for April 12.

"The court action is something we've felt compelled to attempt and I'm very grateful to [lawyer] Peter Rosenthal for pulling it together so quickly," May told Evan Solomon, the host of CBC's Power & Politics, on Sunday. "In this case, it's never been truer that justice delayed is justice denied."

Lawyer Peter Rosenthal said the crux of his argument is that regulations under the Broadcast Act give equitable coverage to political parties during election periods.

"It's our view that recent Supreme Court decisions over the last five or 10 years have indicated that the Canadian Charter of Rights and Freedoms guarantees fairness in elections," he said.

"The evidence that we will put before the court … will show that it cannot be fair and equitable unless [May] is included in the leaders' debate."

It is not clear whether the court will reach a decision before the debate.

"We might not be able to get Elizabeth in the debates," Rosenthal said. "We have to recognize that as a possibility, but I do hope that public opinion and the courts will both say that she must be in."

May said the issue is about much more than just the debate.

"It's about what kind of democracy we have in Canada — who makes up the rules for something as important as a national leaders' debate, and how can we continue to have such an arbitrary, high-handed, closed-door policy?" she said.

"I really think that it's not just the Green Party that will suffer if I'm not in the debates. I think that it will turn a lot of Canadians off this election, they won't watch the debates [and] that will result in lower voter turnout and that's bad for everybody."

May said it is crucial the party be allowed to participate: "We should be back at the table, participating in these debates, and raising issues that frankly I don't think anyone else is going to raise."