House Judiciary ranking member Lamar Smith (R-Texas) has again asked Attorney General Eric Holder to hand over any documents that would confirm his department’s legal conclusion that the D.C. voting rights act is unconstitutional.

Republicans have been pressuring Holder to release any documents related to the issue after it was reported that once the Justice Department’s legal team declared the bill unconstitutional, Holder responded by asking the Office of the Solicitor General for a second opinion. That office reportedly affirmed the constitutionality of the bill, which would give the District a vote on the floor of the House of Representatives.

Earlier this month, Smith sent a letter to Holder requesting a memo from the Office of Legal Counsel that questions the constitutionality of the D.C. vote proposal. Holder responded on April 17 with “substantial concerns— about disclosing documents that would reveal the department’s internal deliberations on legal matters.

On Monday, Smith sent another letter with a narrower request: just the final conclusion of that memo, even if it is only “a single sentence of a much larger document.—

In his letter, Smith says is it “puzzling— why the Justice Department would withhold the document given that department officials have publicly deemed the D.C. voting rights bill unconstitutional “since the Kennedy administration.—

Additionally, the administration recently released OLC memos detailing interrogation tactics during a time of war, Smith said.

“These memos deal with far more sensitive issues, yet the Justice Department was willing to release them. I do not see any reason for the same department to now withhold memos regarding the constitutionality of the legislation in question,— he said.

The D.C. vote bill remains in limbo for now, as pro-gun lawmakers push for an amendment to strip the District of most of its gun laws. House Majority Leader Steny Hoyer (D-Md.) has predicted the bill will get to the floor by the end of May.