The Supreme Court appears ready to make voting more difficult, especially in California. President Donald Trump, Republicans in Congress and even the U.S. Postal Service could compound the problem.

During oral arguments last week, a majority of the justices seemed ready to strike down state laws that allow late-arriving, mail-in ballots to be counted. If that happens, voters will have to mail their ballots days earlier or deliver them in person to ensure their arrival by Election Day.

That would have a tremendous impact in California, where all 23 million registered voters may vote by mail. California, 13 other states and the District of Columbia accept ballots that are postmarked by Election Day but arrive by a later deadline. California’s grace period lasts seven days. It exists for a couple of reasons.

First, it accommodates Americans who live overseas, especially members of the military. The vagaries of international mail could too easily disenfranchise them.

Second, it accommodates voters present in California against the vagaries of domestic mail. The U.S. Postal Service has consolidated its processing facilities and reduced mailbox pickups. That means ballots, income tax returns and other mail might not be postmarked on the same day that someone puts them in a mailbox.

Republicans seek to undo that simple accommodation. The Republican National Committee filed the challenge now before the Supreme Court. It involves Mississippi’s five-day grace period, but if the court’s conservative majority overrules the Mississippi law, the result likely will apply everywhere.

Arguments against a grace period focused on the definition of “Election Day,” whether voters could try to recall ballots after mailing them, the potential for fraud and public perceptions.

Yet numerous investigations have found no significant voter fraud associated with voting by mail or grace periods for receiving ballots.

If public perceptions are negative, they are so because of Republican demagoguery and conspiracy theories, not reality.

California has been a particular target for conservative ire because the state is often slow to finish counting its ballots. There is certainly room for improvement, but the problem is not the grace period. During the 2024 general election, only about 2.5% of all ballots cast statewide were postmarked by Election Day but arrived in the grace period. As we wrote at the time, “No one likes delays, but accurate results are essential to a healthy democracy. That’s worth the wait.”

While the Supreme Court case is underway, Trump and his congressional allies hope to further undermine elections and mail-in voting with the Safeguard American Voter Eligibility (SAVE) Act. The House has passed it, but it has stalled in the Senate so far.

To Trump and Republican supporters of the bill, mail voting is a bogeyman that threatens democracy. “Mail-in voting means mail-in cheating,” he said last week, continuing his rant that the 2020 election was stolen from him and that mail ballots were a prime culprit. Never mind that Trump voted early by mail in a Florida special election this month.

If the Supreme Court strikes down grace periods or the SAVE Act becomes law, they will not improve elections. They only will sow confusion and risk disenfranchising voters. That might well be the goal in a year when Republicans easily could lose control of Congress.

California can counteract some of the impact by maximizing the number of ballot drop boxes in communities so that late voters have a guaranteed alternative to a mailbox.

Mail balloting is convenient, safe and secure. Leaders should encourage its use and seek to expand voter access, not limit it.