On July 31, a Utah state trial court ruled in favor of keeping Celeste Maloy on the September 5 Republican primary ballot. She is running in the special congressional election to fill the vacancy in the Second District. Her ballot status was challenged on the basis that she wasn’t a registered Republican when she filed. This news story says she was not registered at all on that date.
In 1986, the U.S. Supreme Court said that if a party wishes to nominate a non-member, it has a constitutional right to do that. Utah law says no one can run in a primary who is not a registered member of that party.