In Brett Kavanaugh’s long and distinguished career in law, one period stands out as especially important to him.

“People sometimes ask what prior legal experience has been most useful for me as a judge,” Kavanaugh, President Donald Trump’s nominee to replace Justice Anthony Kennedy on the Supreme Court, wrote in Marquette Law Magazine in 2016. “And I say, ‘I certainly draw on all of them,’ but I also say that my five-and-a-half years at the White House and especially my three years as staff secretary for President George W. Bush were the most interesting and informative for me.” Six years earlier, he made a nearly identical statement.

Given these remarks, it’s understandable that U.S. senators would be interested in his work and writings during his tenure in the Bush White House. After all, in the coming months they will be voting on whether to confirm Kavanaugh to a lifetime post on the Supreme Court. From there, he will spend the next three to four decades interpreting the Constitution and shaping the future of American law. Kennedy’s impact, as the court’s swing justice, on the nation’s lives and liberties underscores the gravity of this process and the need for maximal transparency.

Senate Republicans apparently disagree. Chuck Grassley, the Iowa senator who chairs the Senate Judiciary Committee, sent a letter notifying Minority Leader Chuck Schumer last week that he was “not going to put American taxpayers on the hook” by seeking Kavanaugh’s records from his time as Bush’s staff secretary. (He will still request records from when Kavanaugh served in the White House counsel’s office.) It’s unlikely that those records, Grassley wrote, would provide “any meaningful insight” into how Kavanaugh would perform his judicial duties if confirmed to the Supreme Court.

Grassley is set to request from the executive branch more documents related to Kavanaugh than any preceding nominee. But that makes his refusal to request documents related to Kavanaugh’s tenure as staff secretary all the more bizarre. There doesn’t appear to be any reasonable justification to keep those documents out of the public eye before Kavanaugh’s confirmation vote, other than the concerns that you might find something that could prevent it.