House Republicans on Thursday used a procedural motion to block a vote on whether to add an exception for incest to an abortion coverage ban in its criminal justice appropriations bill.

The bill prohibits using federal funds to cover abortion for pregnant women in federal prisons, except if the woman’s life is in danger or if she was raped. Incest is usually mentioned as an exception to other federal abortion funding bans such as the Hyde Amendment, but the criminal justice appropriations bill does not contain such an exception.

Like the Hyde Amendment, the appropriations bill lacks an exception for a woman’s health, excluding many medically necessary abortions that fall short of life-saving.

“Laws have consequences,” said Rep. Alan Grayson (D-FL) on the House floor after introducing an amendment adding incest to the list of exceptions. “The scenario we’re describing here is one where a female prisoner is the victim of incest. If this law passes as currently written, that female prisoner will be forced to carry to term the child of an incestuous relationship. I regard this as absolutely indefensible.”

Rep. Jon Culberson (R-TX) raised a point-of-order objection to Grayson’s amendment on behalf of the Republican caucus, arguing it violated a rule that amendments to appropriations bills cannot “legislate,” or change the existing law.

Grayson acknowledged that the objection could be raised, but urged Culberson to exercise his option not to do so, since other federal funding bans allow exceptions for incest and the drafters of the amendment may have inadvertently left one out.

But Culberson insisted on the point-of-order objection, and the vote on the amendment was blocked.