South Korea's top court has upheld laws that toughened punishment on prostitutes, pimps and their clients. prostitute

The 2004 legislation drove thousands of sex workers in traditional red-light zones out of business in South Korea but prostitution has still thrived in the shadows. Sex workers have occasionally held rallies calling for the laws' abolishment.

The Constitutional Court ruled Thursday to uphold a provision that makes it a criminal offense to voluntarily sell or buy sex, punishable by a year in prison or a fine.

The ruling was made in response to a compliant by a female sex worker, who argued people have the right to choose their occupation.

A court statement says the government could deny such individual rights to prevent exploitation and protect moral values.