A bar owner in Portland, Oregon, was found guilty of discriminating against a group of transgenders after an appeals court upheld a ruling of the state labour bureau.

In a decision issued on Wednesday, the Court of Appeals ruled that Christopher Penner, owner of the bar formerly known as P Club, violated Oregon's law that prohibits private businesses from discriminating based on sexual orientation, according to Reuters.

Oregon was also the state where a gay couple forced a bakery to pay fines and eventually close shop for the owners' refusal to bake a same-sex wedding cake.

The latest case stemmed from two voice-mail messages that Penner left on June 18, 2012 for Cassandra Lynn, founder of Rose City T-Girls, a social club that includes transgender women, cross-dressing straight individuals, homosexuals and lesbians in 2012.

Penner was apologetic but told Lynn and the girls not to come back to the club on Friday nights as their presence was "hurting business a lot" as customers referred the club as a "tranny" or "gay" bar.

Oregon's Bureau of Labor and Industries (BOLI) ruled in favour of the girls and ordered Blachana LLC and Penner to pay $400,000 to the 11 aggrieved persons. BOLI also imposed $3,000 in civil penalties on Blachana LLC and $2,000 on Penner.

Penner had to pay the amount. He eventually closed the bar last year, according to his lawyer, Jonathan Radmacher.

"You can't do business if the state comes in and empties your bank account," he said.

BOLI defended its decision. "Our agency is committed to protecting the civil rights of all Oregonians so that people are not denied employment, housing or access to public places based on who they are or who they love," Labor Commissioner Brad Avakian said in a statement.

Radmacher said Penner is considering his next step after the ruling, adding that his client was punished even though he did not take a religious position and had no intention to discriminate.