The Supreme Court’s current session is likely to prove one of the most important in many years. At the heart of a case the justices will consider is the individual mandate in President Obama’s Affordable Care Act, which requires every American to purchase health insurance. If the Supreme Court upholds the individual mandate, it will set a precedent for future Congresses and expand the federal government’s reach into our everyday lives.

But the outcome of the case is not the only issue of concern to the American people. Interest groups on both sides are calling for the recusal of two Supreme Court justices.

While we don’t know whether these justices should recuse themselves, it is clear that not all of the allegations are equal. For example, some groups allege that Justice Clarence Thomas should recuse himself because of his wife’s involvement with groups opposed to the health-care law.

But concerns about the job or personal views of a justice’s spouse are not the same as concerns that a justice may have been involved in a matter before it reached the high court.

Specifically, Justice Elena Kagan may have played a role in the development and defense of the president’s health-care law during her tenure as U.S. solicitor general. Despite claims from Obama administration officials that Kagan was not involved in the health-care discussions, e-mails released last month indicate that there may be more to the story.

One e-mail shows then-Principal Deputy Solicitor General Neal Katyal telling a public-affairs staffer that Kagan was not involved in any of the discussions or consultations over the legislation.

But in an e-mail dated two months earlier, Katyal forwarded to Kagan information about a meeting at the White House on the health-care law and wrote: “I think you should go, no? I will regardless but feel this is litigation of singular importance.” Kagan responded by asking Katyal for his phone number.

While we don’t know whether Kagan attended that meeting, her response suggests that she discussed it with Katyal over the phone. This exchange of e-mails raises the question of whether she tried to hide her involvement by conducting conversations over the phone to limit any paper trail.

We also know from the e-mails that she personally supported the legislation’s passage. In an exchange with a Justice Department colleague discussing an upcoming House vote on the health-care bill, Kagan exclaims, “I hear they have the votes, Larry!! Simply amazing.”

These e-mails reveal inconsistencies with the administration’s claims that Kagan was completely walled off from this issue. To help clear up any confusion, I have written to the Justice Department and the White House to get additional documents and conduct staff interviews. Unfortunately, the administration’s refusal to cooperate with a legitimate congressional inquiry only heightens the public’s concern.

The NFL wouldn’t allow a team to officiate its own game. If, as solicitor general, Kagan did advise administration officials on the constitutionality of the president’s health-care law, she should not officiate when the matter comes before the Supreme Court.

The Obama administration has a responsibility to fully disclose any information about what role Kagan played in the review of the Affordable Care Act. The validity of the outcome at the high court depends on the impartiality of the justices.

This case is far too important for the White House to refuse to provide the facts to the American people.

The writer, a Republican representative from Texas, is chairman of the House Judiciary Committee.