Christian conservative Tony Perkins has criticized a federal appeal court's finding that workplace discrimination based on sexual orientation violates existing law.

The 7th U.S. Circuit Court of Appeals on Tuesday became the first appeals court to uphold that Title VII of the Civil Rights Act of 1964 protects workers from discrimination based on sexual orientation.

(Related: Appeals court finds existing law protects gay workers from discrimination.)

The debate is likely headed to the Supreme Court.

“If Congress won't rewrite the law, liberals will find a court who will!” wrote Perkins, president of the Family Research Council (FRC) and an early backer of President Donald Trump. “That's been the M.O. of the Left for decades: Packing the bench with wannabe legislators who'll impose the agendas they could never pass democratically.”

Perkins pointed out that Congress has rejected bills that sought to prohibit workplace discrimination based on sexual orientation and gender identity, though he did not mention the successes LGBT advocates have had passing local and state laws throughout the country.

“In a mind-boggling decision yesterday, the judges not only stole Congress's job – they admitted they were doing it!”

“The decision, an 8-3 bombshell, was astounding because it bucked – not just the 7th Circuit’s precedent, but every circuit’s precedent,” added Perkins, a vocal opponent of LGBT rights.