The Board of Internal Economy has concluded that the NDP inappropriately spent tax dollars when it employed staffers in the party’s satellite offices and must pay that money back, Conservative MP John Duncan said Tuesday.

Duncan said the board has instructed House of Commons administration to look into options for recovering the money because the NDP’s satellite offices were not authorized. He said the board does not have the total amount, but it will be “significant” since it involves salaries paid out since the fall of 2011.

“The rules are clear and it is clear that once again, the NDP has broken the rules,” Duncan told reporters.

The multi-party BOIE -- which governs the financial and administrative policies of the House of Commons -- had met behind closed doors to discuss the issue after the NDP was accused of improperly using parliamentary resources.

The board had previously ruled that the NDP broke rules governing free mailing privileges and ordered the party and MPs to repay $1.17 million. The NDP is appealing that ruling in court. The sum for the salaries would be on top of that $1.17 million.

The NDP was accused of using its parliamentary budget to pay staffers for partisan work in the party’s Montreal and Quebec City satellite offices.

NDP Leader Thomas Mulcair has insisted that the party did nothing wrong and that Commons officials had approved the use of satellite offices. But House Speaker Andrew Scheer told a committee in May that no one from the NDP approached him about the offices.

Duncan said Tuesday the New Democrats have not provided sufficient information to determine whether the satellite office employees were doing constituency or parliamentary work.

He also said the BOIE will refer the matter to Elections Canada because “there is some indication” that some employees of a satellite office worked on the NDP’s byelection campaign in the Montreal riding of Bourassa.

House of Commons employees are not allowed to work on election campaigns unless they take a leave of absence.

NDP House Leader Peter Julian issued a statement Tuesday after the board’s findings were made public, accusing the BOIE of acting like a “kangaroo court.”

“These decisions were made behind closed doors – far from media and public scrutiny – and without any regard for fundamental justice or the rule of law,” Julian said. “Several MPs were retroactively found guilty, without any knowledge of the nature of the charges being brought against them or any opportunity to defend themselves.”

He maintained that no public funds were inappropriately used, and accused the Liberals and Conservatives of teaming up against the NDP.

“These two parties deliberately chose to tarnish the reputation of outstanding parliamentary staff, who now find themselves in limbo and at risk of losing their jobs,” he said.

The decision could cost the party millions of dollars. The NDP will have to repay three years’ worth of salaries -- as well as all the expenses -- for the two-dozen or so employees caught up in the board’s ruling.

Some of those employees have since moved to Mulcair’s office in Montreal, where they continue to work.

“As far as I know, we're not getting fired today and nothing seems to indicate that way,” said one NDP press secretary. “But it sure is not fun.”

The board will also have to decide who will be reimbursing taxpayers – the party or the individual MPs who hired to the staffers.

Julian said the NDP will take time to consider its options before it responds to the BOIE findings.

Earlier Tuesday, NDP whip Nycole Turmel also accused the board of being partisan and refusing to listen to evidence presented by the NDP in its defence.