Mail-in ballots are arriving across Sacramento County for the Proposition 50 special election, and some voters say they’ve noticed something that worries them — small holes in their ballot envelopes.

Allen Wegat, one of those voters, said the holes could allow someone to see or even tamper with his vote, CBS News reported.

“If someone were unscrupulous and didn’t like how I voted, they could double-mark it, which would invalidate my vote,” Wegat said. “It makes it too easy for bad actors.”

Sacramento County’s vote-by-mail envelope design includes small circular holes on each side. When the ballot inside is folded a certain way, the marked bubble for Proposition 50 could become faintly visible through those holes.

“The back of the card is left blank,” Casparis explained. “Just fold it, you’ve got nothing on either side of this, stick it in your ballot envelope.”

Election officials say the holes are not new and are standard practice across California. They’ve been part of the envelope design for years to help workers verify that envelopes are empty after processing and to assist visually impaired voters in locating where to sign.

Casparis said there are several ways to insert a ballot card into the envelope, and only a couple of those would make any markings visible. He said anyone concerned about privacy can simply fold the ballot so the blank back side faces outward before sealing it.