(Bloomberg) -- Arizona Attorney General Mark Brnovich acknowledged that his suit challenging the Biden Administration’s announced Covid-19 vaccine requirements for many U.S. workers is unlikely to succeed because the actual rules haven’t been finalized.

“Is it a long shot? Yeah, I recognize that,” Brnovich, a Republican former federal prosecutor who is running for U.S. Senate in 2022, said in a phone interview. “But I also think these are very important principles to be fighting for.”

Brnovich’s 14-page complaint this week was the first to be filed by a state attorney general after President Joe Biden said on Sept. 9 that he would require many private employers to mandate vaccinations or weekly testing for workers. The actual rules are to be developed by the Occupational Safety and Health Administration, and other Republican attorneys general signaled that they’d wait until those are introduced before going to court.

The Arizona suit, which seeks a preemptive ruling that the proposed vaccine requirements are illegal, is almost certain to be dismissed by a federal judge because there are no actual mandates yet, making the dispute unripe.

‘False Choice’

Brnovich, 54, said his suit claims that Biden’s executive order violates the Constitution’s Equal Protection Clause because the vaccine is optional for undocumented immigrants at the U.S. border while being mandatory for American workers. The option for U.S. workers to get regular tests instead of the vaccine is a “false choice,” he said.

“People shouldn’t be put in a position where they’re jeopardizing their livelihood, or they’re jeopardizing their job or they’re ostracized or they’re outcast because they won’t do something that the president doesn’t have the ability to make them do,” Brnovich said.

Biden argues the mandate is a crucial part of the fight against the coronavirus, which has sickened millions and killed more than 650,000 people in the U.S. Similar state and local rules have divided the country along political lines, even as the delta variant of the virus continues to flood hospitals and morgues, mostly with the unvaccinated.

Though Brnovich was the first Republican to the courthouse, he certainly won’t be the last. There are “many more lawsuits to come,” he said.

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