Ex-Greens boss says change constitution

Former Australian Greens leader Christine Milne believes there is a clear case to change the constitution to clear up the citizenship fiasco.

Ms Milne, ahead of the launch of her memoir An Activist Life on Tuesday, said it was "total chaos" in Canberra.

"What is going on now is a serious risk to democracy because the community is overwhelmingly losing faith in the political process to act in the best interests of the country," the former Tasmanian senator said.

"I think it is a constitutional crisis that we are now in."

Ms Milne said it was clear Prime Minister Malcolm Turnbull and Labor leader Bill Shorten were "protecting people" in the House of Representatives, despite two coalition MPs facing by-elections.

"It does not pass any kind of pub test to say that it's only senators," she said, adding that it was a fair call for Greens MP Adam Bandt to help the coalition refer Labor MPs to the High Court.

In the long-term, however, section 44 of the constitution must be changed.

That section says a person is incapable of being elected to federal parliament if they are "a subject or a citizen or entitled to the rights or privileges of a subject or a citizen of a foreign power".

The section caught out former Greens senators Scott Ludlam and Larissa Waters.

The High Court has ruled it covers people who find they are citizens by descent.

"It is just not right that we have a young country, a multicultural country, that has this hangover and is disenfranchising a lot of people," the fifth-generation Tasmanian said.

"There has to be the commitment to Australia and advancing Australia, but if it is going to go back to grandparents and so on, there's going to be hardly anyone left."