US lawsuit claims chimpanzees are 'legal persons'
4 December 2013 Last updated at 11:42 GMT
The animal rights group The Nonhuman Rights Project has filed a lawsuit in the United States to establish a chimpanzee as a "legal person".
The group's president, Steve Wise, told the BBC Radio 4's Today programme that he is specifically filing lawsuits on behalf of the "four surviving chimpanzees in the state of New York" so that they have the right to no longer be "imprisoned".
"We are asking the courts to remove them to a sanctuary," where they would be "as free as they can be in North America".
He added: "We have consciously modelled [the lawsuit] upon the way both British and American courts dealt with black slaves in the 18th and 19th centuries who sought freedom.
"Under the theories that we're proposing before the court, the species is not relevant at all."
First broadcast on BBC Radio 4's Today programme on Wednesday 4 December 2013.