Australian Greens MP Adam Bandt and independent MP Andrew Wilkie expressed frustration that the fight between the two major parties was taking up time when parliament could be passing marriage equality law.
Neither is a member of the government, but the outcome of Ms. Gallagher's case in particular, which rests on whether she made "reasonable steps" to renounce her British citizenship, will set a precedent that could later unseat government members.
Those that were flagged in the Labor motion to be headed for the High Court were Labor MPs David Feeney, Josh Wilson, Justine Keay and Susan Lamb; Liberal MPs Nola Marino, Alex Hawke, Jason Falinski and Julia Banks; and NXT MP Rebekha Sharkie.
Labor has been dealt a further blow in the citizenship crisis, with Victorian MP David Feeney flagging his status is likely to go to the High Court because evidence can not be found that he renounced his British citizenship.
If the resolution is successful, the nine MPs would be referred to the High Court to determine their eligibility to sit in parliament.
The citizenship saga distracted MPs from the debate on same-sex marriage legislation on Wednesday, with the opposition seeking crossbench support for nine MPs to be checked for their eligibility.
Supporting the motion, Attorney-General, George Brandis, said it did not reflect on the integrity of Katy Gallagher, but on the integrity of Opposition Leader, Bill Shorten.
These MPs had not provided the needed evidence to prove they weren't dual citizens, he said.
For Labor MP Susan Lamb, it is unclear if she was ever even eligible to take up United Kingdom citizenship.
German trains collide in Meerbusch, several injured
While a rescue operation was launched immediately, authorities have said the injuries people suffered were not life-threatening. Five people were injured in a train collision in a city close to Dusseldorf on Tuesday, local fire department said.
He revealed Labor was even prepared to refer to court Environment and Energy Minister Josh Frydenberg, whose parents arrived in Australia stateless after escaping the Nazis.
"The British Home Office took many, many weeks months to be able to process their applications", Mr Burke said. "I stand by that position", she said.
In October, the High Court disqualified five MPs and Senators, including Deputy Prime Minister Barnaby Joyce, who found that he had New Zealand citizenship.
The embattled Prime Minister has a strong likelihood of picking up three seats out of a potential Super Saturday of by-elections early next year, given Ms Sharkie is also likely to be referred.
Senator Gallagher lodged paperwork, in line with a new parliamentary register of citizenship, on Monday confirming she completed a British citizenship renunciation form, with payment, on April 20, 2016.
Crucially, the government had regained Mr Joyce's vote on Wednesday for the first time since his by-election.
"Based on all the advice I have available to me, I do not believe that I should refer myself to the Court of Disputed Returns", Senator Gallagher said.
"The Australian people are sick of this constitutional crisis, the only way to resolve this citizenship crisis is with the cooperation of all sides of parliament", he said.
She said the Coalition has tried to attack her eligibility and reputation and she wanted the matter resolved, which is why she asked for it to be sent to the High Court.