Alabama Republican Senate nominee Roy Moore reacted to the groping allegations made against Minnesota Democratic Sen. Al Franken on Thursday by arguing a double standard is at play.

In a tweet, Moore, who is facing calls to drop of the Senate race after multiple women have accused him of sexual misconduct in the past, attacked Senate Majority Leader Mitch McConnell over his differing responses.

Moore tweeted: “Al Franken admits guilt after photographic evidence of his abuse surfaces. Mitch: ‘Let's investigate.’ In Alabama, ZERO evidence, allegations 100% rejected. Mitch: ‘Moore must quit immediately or be expelled.’”

McConnell, the Republican leader, on Thursday called on the Senate Ethics Committee to investigate Franken.

“As with all credible allegations of sexual harassment or assault, I believe the Ethics Committee should review the matter,” McConnell said. “I hope the Democratic leader will join me on this. Regardless of party, harassment and assault are completely unacceptable—in the workplace or anywhere else.”

McConnell has called on Moore to withdraw from the Alabama race and has explored options for backing an alternative Republican to run for the seat.