Authorities are warning taxi drivers of hefty fines if they are caught without socks, shoes and the other proper attire prescribed by a licensing board, an official said Monday.

The dress code requires taxi drivers to tuck in their shirts — which have to be white, not the beige that many have been wearing.

Pants must be dark, no sandals are allowed, and shoes must be leather ones worn with socks, said Commercial Vehicle Licensing Board chairman Markiman Kobiran.

"Even though it's trivial, it reflects the entire profession," Markiman told The Associated Press.

He said the board can fine drivers who do not dress properly up to $87.

Richard Leow, secretary of a local taxi drivers' association, said the fine was too high given that taxi drivers only earn about $20 a day.

Leow said one of his drivers received the maximum fine last week for wearing jeans.

"This is too much. I saw him, and he was dressed very neatly. The passenger cannot even see the drivers' pants," he said. "(The board) is really harassing all the drivers. This is unreasonable."