Justice department lawyers will revive legal arguments advanced by the former Harper government to try to block a lawsuit by six Afghan war veterans intent on restoring pensions for injured and wounded soldiers.

CBC News first reported last month that the federal government is taking veterans involved in the Equitas lawsuit back to court to try to block certain benefits for soldiers, despite a Liberal campaign promise to better support them after an era of Conservative cuts.

A peace agreement of sorts, reached by former veterans affairs minister Erin O'Toole, recently expired without any sort of resolution meaning the litigation will now proceed at the B.C. Court of Appeals.

The government's handpicked lawyers will argue that Canada does not have a social contract or covenant with veterans, and that a "scheme providing benefits cannot be said to amount to a deprivation merely because claimant views the benefits as insufficient."

The plaintiffs have argued in court that the lump-sum payment wounded veterans receive under the New Veterans Charter — as opposed to the lifetime pension that was offered to veterans before 2006 — is inadequate compensation, as they receive less money over a lifetime.

In court documents filed this week, the government's top class action lawsuit lawyer, Paul Vickery, said that "the submissions made by [former Conservative attorney-general Rob Nicholson] on hearing of the appeal, as set out in the factum filed by him, accurately reflect the current position of the federal government."

That is a controversial position among many in the veterans community as there is a long-held belief that Canada has a special responsibility to its veterans — a social contract — based on the promise politicians have made for generations to adequately care for those soldiers who are hurt in the line of duty.

Conservative Veterans Affairs Minister Erin O'Toole repudiated the argument made by government lawyers that there is no social contract, or covenant, between Canada and injured war veterans. (Sean Kilpatrick/Canadian Press)

"No set of principles exist that can be stated with certainty, understood with clarity, or accepted with unanimity among the people of Canada to define a 'social contract' or 'social covenant' as alleged," the government lawyers argued in 2014, adding there is no fiduciary duty "to place the interests of disabled veterans above the interests of all other Canadians."

Those arguments were later repudiated when O'Toole was brought in to replace the embattled Julian Fantino, who had a fractious relationship with veterans groups.

O'Toole removed Vickery from the case and replaced him with Joel Watson, a litigator from the private sector and himself a former veteran. But after the Liberals defeated the Conservatives last October, the new veterans affairs minister, Kent Hehr, put Vickery back in charge.

"I cannot discuss the specifics of an ongoing court case," Hehr said in a recent statement to CBC News.

The case returns to court on Friday.

Trudeau promised lifetime pensions

The Liberal platform in the last election explicitly promised to restore the pension benefit. "We will re-establish lifelong pensions as an option for our injured veterans, and increase the value of the disability award," the platform reads. Prime Minister Justin Trudeau reaffirmed that commitment in a stump speech on the campaign trail.

The promise was also included in Hehr's mandate letter from the prime minister, but was notably absent from the government's first budget introduced in March, although the government did make substantial new funding commitments to other veterans programs.

Veterans Affairs Minister Kent Hehr speaks with veterans at the Canadian War Museum. A legal truce over the New Veterans Charter is in danger of falling apart, as government lawyers threaten court action, according to a letter obtained by CBC News. (Justin Tang/Canadian Press)

Moreover, all parties voted unanimously in favour of a motion introduced by NDP MP Fin Donnelly last May, which recognized a "stand-alone covenant of moral, social, legal and fiduciary obligation exists between the Canadian people … and members of the Canadian Armed Forces who have been injured, disabled or died as a result of military service."

Don Sorochan, the lawyer representing the veterans, said it would be the height of hypocrisy if the Liberal government now rejects those principles in court.

Resolution symbolic, Liberals argue

But government lawyers will do exactly that, according to their memorandum, arguing that the resolution was largely symbolic and does not oblige the government to provide pensions to injured veterans.

"The House of Commons motion referred to by the plaintiffs, while it records the opinion of the then members of Parliament on the matters referred to in the motion, does not have the force of law and cannot bind the federal government," the lawyers wrote.

Sorochan has said that the appeal court should not render a decision in the case without hearing additional evidence, namely that the Liberals explicitly campaigned on restoring pensions and voted for Donnelley's motion. He said the original Harper-era appeals case, from December 2014, is outdated and does not reflect the change in governance.

But the government lawyers batted that suggestion away, saying the plaintiffs have no right to introduce evidence at this stage of the legal proceedings.

"It is not open to the plaintiffs to attempt to introduce evidence on the appeal, since the appeal is from an order made on a pleadings motion, in which no evidence may be tendered," the memorandum reads.

Follow John Paul Tasker on Twitter @JPTasker