See more of our coverage on recent attacks against Planned Parenthood here.

The U.S. House is expected to vote Thursday on a bill to defund Planned Parenthood for one year unless it stops offering abortion care.

The bill, the Defund Planned Parenthood Act of 2015, is sponsored by Rep. Diane Black (R-TN). It’s one of many such proposals Republicans have offered in the months after an anti-choice front group released deceptive videos claiming that Planned Parenthood broke the law while contributing to fetal tissue research.

The bill aims to put a temporary moratorium on funding while Congress finishes investigating Planned Parenthood.

So far no state-level investigations have found Planned Parenthood guilty of any wrongdoing. A preliminary report from one congressional committee has also found no evidence that Planned Parenthood broke the law.

Black’s defunding bill faces two major challenges.

One is that while it will likely pass the Republican-dominated House, the 60-vote threshold to break a filibuster in the Senate is almost sure to stop it. Even if it passed both houses of Congress, President Obama would veto it.

The other problem is that “defunding” Planned Parenthood is much easier said than done, since most of its government funding comes in the form of mandatory Medicaid reimbursements.

Planned Parenthood also would not cease operations in the event of a government shutdown.

Black’s bill wouldn’t force a government shutdown, unless it got attached to a mandatory spending bill. Black has said she doesn’t favor a shutdown threat as a tactic, but dozens of right-wing Republicans are threatening to vote against any spending bill that funds Planned Parenthood.

If Congress can’t pass a spending bill that Obama will sign by September 30—and Obama is sure to veto anything defunding Planned Parenthood—the government will shut down.