Photo: Carrie BraesConservatives are mad at Sen. Lisa Murkowski for opposing the confirmation of Brett Kavanaugh to the U.S. Supreme Court. But some liberals were mad at her, too, because technically, she didn’t vote “no” on Kavanaugh. She voted “present.”Listen nowFrom the left have come accusations that Murkowski chickened out, that she dodged a hard vote by taking refuge in an obscure Senate procedure.Lucky for us, the Senate employs historians.“We are the institutional memory of the Senate,” said Dan Holt, assistant historian at the Senate Historical Office.Holt said senators have been pairing votes since at least 1859, as a courtesy to each other. If one senator had to miss a vote, another senator who wanted to vote the opposite way would abstain.Dating back to the 19th century, the custom fit with the Senate’s view of itself, as a place where gentlemen wouldn’t want to take unfair advantage.Dan Holt, assistant historian at the U.S. Senate. Photo: Liz Ruskin“They, I think, mostly thought it would not be fair if a vote would go one way or the other, just because some senators were absent,” Holt said.Murkowski’s action on the Kavanaugh nomination was a perfect example of a paired vote, Holt said.As she explained on Senate floor, Murkowski paired with Sen. Steve Daines, R-Mont, so he could attend his daughter’s wedding that weekend.“If he were present and voting, he would have voted aye. I have voted no,” she said. “The pair will not change the outcome of the vote. I therefore withdraw my vote.”Hold, the historian, said the practice used to be far more common, in part because senators used to miss a lot more votes, back when many tried to keep their law offices open and constituents didn’t make a thing out of absenteeism.“It definitely tapered off in the 1980s and 1990s but there are still examples of it if you search the Congressional Record, even into the 2000s,” Holt said.The late Sen. Ted Stevens would sometimes pair votes with Sen. Daniel Inouye, D-Hawaii.“I ask that the last vote be amended to show that I stated I did have a pair with the senator from Hawaii,” Stevens said on the floor in 2005, after a different judicial confirmation vote. “If he were present he would have voted no. I would have voted aye. And therefore I’d like the record to reflect that that was a paired vote. It would not change the outcome of that vote.”A key element for vote pairing is to state for the record how the senators would have voted, if they weren’t paired, Holt said, so it’s not an effective way of avoiding a tough vote.“It’s the exact opposite,” he said. “The senator wants to make sure that their position goes down into the record, even if they can’t be present.”Murkowski may have confounded some of her constituents with the paired vote. A poll by Alaska Survey Research shows her favorability rating dipped the week of the Kavanaugh vote, even among self-identified moderates and progressives. But a follow-up poll suggests Alaska voters are back to where they were before, with about half saying they have a positive view of the senator.