Updated: 4:06 p.m.

In continuing their campaign against the new health care law, 28 Republican Representatives, including top GOP House leadership, Tuesday signed on to an amicus brief filed in support of Virginia’s constitutional challenge to the law.

The American Center for Law and Justice, a conservative public interest law firm, filed the friend-of-the-court brief in the U.S. District Court for the Eastern District of Virginia in Richmond in the case of Commonwealth of Virginia v. Kathleen Sebelius, Secretary of the Department of Health and Human Services.

Minority Leader John Boehner (Ohio), Minority Whip Eric Cantor (Va.), House Republican Conference Chairman Mike Pence (Ind.) and Conference Vice Chairwoman Cathy McMorris Rodgers (Wash.) all signed on to the brief contending that the law’s individual mandate to buy health insurance is unconstitutional.

The Members “are dedicated to the founding principles of limited government, and to the corollary precept that the Commerce Clause contains boundaries that Congress may not trespass no matter how serious the nation’s healthcare problems,” according to the brief. They “believe that the individual insurance mandate provision of the [law] exceeds any power granted under the Commerce Clause.”

“Congress cannot pass just any law that seems most efficiently to address a national problem,” the brief continues. “Every federal law must derive from one of the grants of authority found in the Constitution. This the individual insurance mandate does not do.”

Other Members who are part of the filing are: Reps. Paul Broun (Ga.), Todd Akin (Mo.), Rob Bishop (Utah), Michael Burgess (Texas), Dan Burton (Ind.), Mike Conaway (Texas), Mary Fallin (Okla.), John Fleming (La.), Virginia Foxx (N.C.), Trent Franks (Ariz.), Scott Garrett (N.J.), Louie Gohmert (Texas), Bob Goodlatte (Va.), Jeb Hensarling (Texas), Walter Jones Jr. (N.C.), Steve King (Iowa), Doug Lamborn (Colo.), Bob Latta (Ohio), Michael McCaul (Texas), Jerry Moran (Kan.), Jean Schmidt (Ohio), Lamar Smith (Texas), Todd Tiahrt (Kan.) and Zach Wamp (Tenn.).

Boehner spokesman Michael Steel said, “Boehner believes that the job-killing individual mandate in ObamaCare is unconstitutional. He supports the small business leaders and more than 20 states that are suing to overturn it.”

Cantor spokesman Brad Dayspring said, “Mr. Cantor believes the law is unconstitutional and hopes that it is reversed before the states throw too much money down the tubes and replaced by a constitutional law that lowers health care costs and allows patients and families to keep the health care they have if they like it.”