JAPANESE police are facing a lawsuit this week over its racial profiling of black and ethnic minority residents with overseas ancestry.

A civil case opened up today with emotional testimony from plaintiffs who said they were constantly stopped and questioned without good reason.

The case, filed in January by three people against the national government and police and the Tokyo and Aichi forces, claims their treatment constitutes discrimination and violates their human rights.

Japan does not have any anti-discrimination or anti-racial profiling laws.

The government and the police deny they discriminate and say they are just doing their jobs.

Plaintiff Syed Zain, a Japanese citizen of Pakistani descent, said outside Tokyo District Court: “We are relaying our feelings, our experiences and our views.”

Mr Zain said he has been treated like a criminal, despite having lived in Japan for two decades and being fluent in the language.

Black American Maurice Shelton said he has been stopped by police about 17 times during his 10 years living in Japan.

Lawyer Motoki Taniguchi said police frequently stop or question individuals based on race, skin colour or ethnic origin, rather than objective evidence.

A verdict is expected in about a year.