Four top House Democrats said Tuesday that Kansas Secretary of State Kris Kobach (R) should resign from his position as vice chair of President Donald Trump’s commission to investigate elections, arguing that Kobach is using his position for political gain and violating federal transparency and privacy laws.

The request to Vice President Mike Pence, the commission’s chair, came in the form of an 11-page letter from Reps. Elijah Cummings (Md.), John Conyers (Mich.), Bennie Thompson (Miss.) and Robert Brady (Pa.). They are respectively the ranking members of the committees on oversight and government reform, judiciary, homeland security and House administration.

The request comes ahead of the panel’s first meeting on Wednesday and as it faces a handful of lawsuits, accusing it of not conducting a privacy impact assessment and of violating the Federal Advisory Committee Act, which requires that the commission’s work be done in view of the public. Kobach is also facing a separate complaint accusing him of touting his work on the commission to advance his gubernatorial campaign in Kansas, which would be a violation of the Hatch Act. A Kobach spokeswoman earlier this month said she was certain no violation had occurred.

“Mr. Kobach has repeatedly claimed, falsely, that widespread voter fraud exists and advertises his work on the Commission to promote his own campaign for governor of Kansas,” the four congressmen wrote in their letter to Pence. “These actions undermine the integrity of the Commission and raise significant concerns the Commission will be used as a tool for voter suppression.”

In court filings, lawyers for the commission have argued that it is not a federal agency and thus is not subject to federal transparency or privacy protections.

Lawyers have also said the commission is only seeking publicly available information from states. In a June 28 letter to state officials, Kobach did indeed only request public information, but there has been widespread and bipartisan backlash to his efforts, with some states refusing to comply altogether. Colorado Secretary of State Wayne Williams (R) has said more than 3,700 voters in his state ― most of them Democrats ― have deregistered since Kobach’s request.

Neither the White House nor Kobach responded to a request for comment.

Kobach has a long history of raising alarms about supposed voter fraud, but has failed to produce evidence to substantiate his claims. The commission plans to collect data from every state and compare it against federal databases to try and flag voters who are improperly registered. Experts have raised concern that such a process could produce many false positives.

Critics also fear the commission is a way for Trump to lay the groundwork for more restrictive voting laws, like a proof-of-citizenship requirement that Kobach produced in Kansas. In November, Kobach wrote an email to a Trump transition official saying he had begun drafting a plan to amend federal voter law to make a proof-of-citizenship requirement permissible.