Ellen Weintraub, a federal election commissioner, is renewing her demand that President Donald Trump release evidence to support his claim that there was widespread voter fraud in New Hampshire during last year’s presidential election.

Trump has made the claim since November, though he’s released no evidence to support that assertion. New Hampshire officials have refuted that there was widespread voter fraud in the state.

Weintraub wrote a letter to Trump on Wednesday saying that the claim undermined America’s democratic process. In February, Trump claimed that he would have won New Hampshire in the election if thousands hadn’t been bused in. Weintraub argued that the claim fell within the purview of the FEC because if busing did occur no campaign had filed an expense for busing with the agency. Weintraub made a similar call for Trump to release proof of voter fraud in February.

“This allegation of a vast conspiracy, involving thousands of people committing felony criminal acts aimed at stealing the election, has deeply disturbed citizens throughout America. I have heard from many of them, including proud and patriotic New Englanders who are shocked by the allegation and feel that it impugns their historic role in our democracy,” she wrote in her Wednesday letter.

As several states across the country move to pass voting restrictions, Weintraub urged Trump to consider the weight that his allegations carry.

“As the President of the United States of America ― our head of government and head of state ― your words carry considerable persuasive and legal weight. Because of the trust that Americans place in their presidency, some lawmakers around the country may be tempted to rely on your words and move forward with unwarranted voter restrictions,” she wrote. “Indeed, this could result in deterring or preventing American citizens from voting.”

Trump has tapped Vice President Mike Pence to lead a national investigation into voter fraud. The White House hasn’t yet contacted top elected officials in different states about that effort and top Republicans in Congress have said they don’t have evidence of fraud.

“This country should make policy based on facts, not unsupported statements, no matter how high-ranking the source. In these polarized times, we will never be able to find common ground on sound policy going forward if we are operating on different assumptions of what occurred in the recent past,” she wrote. “Our democracy depends on the American people’s faith in our elections. Your voter-fraud allegations run the risk of undermining that faith.”

“Facts matter, Mr. President,” she continued. “The American people deserve to see your evidence.”