Several US academic organisations have filed a complaint against the US Government for excluding a South African scholar from the country.
The American Civil Liberties Union made the complaint on behalf of the American Sociological Association and the American Association of University Professors over the treatment of Adam Habib, deputy vice-chancellor of research, innovation and advancement at the University of Johannesburg.
Professor Habib, a critic of the war in Iraq, travelled to the US frequently until October 2006, when his visa was revoked without explanation after he arrived at a US airport, the ASA said.
It added that he has filed for other visas since then, but has had no explanation of why he has not been given a new one. The lawsuit presses the US Government to make a decision on his visa and argues that exclusion violates his right to free speech.