WASHINGTON — A group of lawmakers objected Thursday to what they describe as the politicizing of two ongoing government reviews of Democratic presidential candidate Hillary Clinton’s e-mail practices.

Four Democratic senators and three House members sent a letter to Intelligence Community Inspector General Charles McCullough and State Department Inspector General Steve Linick. The inspectors general are conducting separate reviews of whether then-Secretary of State Clinton and her top aides mishandled sensitive information in e-mails that passed through a private server in the basement of her New York home.

Republicans have sought to make Clinton’s e-mail use a key issue in the presidential race, and in a debate this week the former secretary again defended her decision to use a private server to handle her work e-mail. While Clinton has conceded her e-mail setup was a mistake, she denies government secrets were ever endangered.

The Democrats, Senate Intelligence Committee Vice Chairman Dianne Feinstein of California and Senate Judiciary Committee Ranking Member Patrick Leahy of Vermont, questioned whether the investigations are being conducted in an impartial manner. They also chided the inspectors general for past errors in determining what material should be marked as classified.

“Based on public reports and communications from your offices to Congress, we have serious questions about how this review is being conducted,” the lawmakers wrote to McCullough and Linick. “Already, this review has been too politicized. We are relying on you as independent inspectors general to perform your duties dispassionately and comprehensively.”

Doug Welty, a spokesman for the State Department’s inspector general, denied that partisan politics play any role.

“At all times, State OIG operates as an independent organization, consistent with the law,” Welty said. “Our work will continue to be unbiased, objective and fact-based. We are now reviewing the e-mail practices of the current and last four secretaries of State, not just Secretary Clinton.”