Republicans file their suit against the Affordable Care Act

(Story updated at 8:10 p.m. ET.)

House Republicans filed their long-awaited lawsuit Friday challenging the Patient Protection and Affordable Care Act.

The lawsuit, filed against the secretaries of HHS and the U.S. Treasury, contests President Barack Obama's decision to waive the healthcare law's employer mandate and the penalties for failing to comply with it without first receiving Congressional approval for the change. That mandate will ultimately require companies with 50 employees or more to provide healthcare coverage to employees.

The lawsuit also argues that the administration is illegally using funds from a separate Treasury Department account meant for other purposes to pay insurance companies $178 billion over the next 10 years as part of the so-called cost-sharing portion of the law. Under the provision, the government pays part of the out-of-pocket costs for low-income beneficiaries to limit their spending.

The House passed a resolution in July authorizing the lawsuit, which was filed in the U.S. District Court for the District of Columbia.

“Time after time, the president has chosen to ignore the will of the American people and re-write federal law on his own without a vote of Congress. That's not the way our system of government was designed to work,” House Speaker John Boehner said in a statement Friday. “If this president can get away with making his own laws, future presidents will have the ability to as well.”

A White House spokesman, however, criticized the legal challenge.

"I think the American people want Washington focused on jobs and the economy—the House Republicans choose to sue us, sue the President for doing his job. And using taxpayer resources at the same time, for a lawsuit that their own congressional research service could not identify any merit for,” White House deputy press secretary Eric Schultz told reporters Friday.

House Democratic Leader Nancy Pelosi also called the lawsuit meritless.

“This lawsuit is a bald-faced attempt to achieve what Republicans have been unable to achieve through the political process,” Pelosi said in a statement. “The legislative branch cannot sue simply because they disagree with the way a law passed by a different Congress has been implemented.”

Ultimately, it will be up to the courts to decide the lawsuit's merits.

One of the first issues House Republicans will likely face will be whether they have standing to sue, constitutional law experts say. To have standing to sue in federal court, House Republicans must show they, in particular, were injured by the president's actions; that the harm was from illegal conduct; and that the outcome they're seeking will provide relief from those injuries, said Todd Gaziano, a senior fellow in constitutional law with the Pacific Legal Foundation, which has filed its own lawsuit challenging the ACA.

Gaziano said he believes the House GOP does have standing.

But Tim Jost, a law professor at Washington and Lee University, said House Republicans have “not been injured in any way.” He called it a “political dispute.”

According to the lawsuit, the government's actions “injure the House by, among other things, usurping its Article I legislative authority.”

As to the merits of the arguments themselves, experts have varying opinions.

Gaziano called the complaint stronger than he imagined it would be. He said the allegation that the government violated the law in spending money through the cost-sharing provision seems stronger to him than the first allegation over the employer mandate.

But Jost said the “law is clear that the [executive branch] is supposed to make these payments.”

Much of the lawsuit comes down to whether Obama overstepped his authority relative to the two actions cited by the House GOP.

“Of course he's overstepped,” Gaziano said of Obama. “The president couldn't get those technical fixes, so he just decided to rewrite statute.”

Others, however, disagree. Erwin Chemerinsky, dean of the University of California Irvine School of Law, called the lawsuit a “publicity stunt.”

“The Republicans who have voted repeatedly to repeal the Affordable Care Act are suing to complain that a part was not implemented fast enough,” Chemerinsky said. “The President can decide to delay enforcement of a law. That is what he did here.”

Since passing their resolution in July, House Republicans have hired three lawyers to represent them in the case, but the first two dropped out, Politico originally reported. George Washington University Law School professor Jonathan Turley announced on his blog earlier this week that he is now representing House Republicans in the case.

Turley noted that he supports national healthcare and voted for Obama before his first term, but said this case: “represents a long-overdue effort by Congress to resolve fundamental Separation of Powers issues. In that sense, it has more to do with constitutional law than health care law.”

A number of cases centering on the Affordable Care Act are now working their way through the courts. The U.S. Supreme Court recently agreed to hear King v. Burwell, which addresses the question of whether insurance premium subsidies should be legal in states that have not established their own exchanges and are instead relying on HealthCare.gov.

Follow Lisa Schencker on Twitter: @lschencker