The founder of Wikipedia has thrown his support behind Richard O'Dwyer, a British student who is due to be extradited to the US on copyright charges.
Jimmy Wales, 45, came out in support of Richard O'Dwyer, 24, who faces up to 10 years in prison if convicted of charges relating to his website, TVShack.net, which linked to other sites that streamed pirated television programmes.
Mr O'Dwyer's supporters argue that as the site did not host material itself he should not face any charges and should therefore not be extradited.
Mr Wales, in a petition on the Change.org website, said TV Shack was "similar to a search engine".
Mr Wales, who has met Mr O'Dwyer, called on Home Secretary Theresa May to stop the extradition, which was approved by a district judge in January, calling the interactive media and animation student "the human face of the battle between the content industry and the interests of the general public".
"O'Dwyer is not a US citizen, he's lived in the UK all his life, his site was not hosted there, and most of his users were not from the US," he wrote.
"America is trying to prosecute a UK citizen for an alleged crime which took place on UK soil.
"The internet as a whole must not tolerate censorship in response to mere allegations of copyright infringement. As citizens we must stand up for our rights online."
And writing exclusively in The Guardian, Mr Wales said: "When I met Richard (along with his mother), he struck me as a clean-cut, geeky kid. Still a university student, he is precisely the kind of person one can imagine launching the next big thing on the internet.
"Enthusiastic, with a sharp mind and a quick wit, he reminds me of many great entrepreneurs. He tried to follow the law, and I would argue that he very likely succeeded in doing so."
Mr Wales described the extradition as an "outrage" and argued that the Mr O'Dwyer, from Bolsover in Derbyshire but studying in Sheffield, always did his best to play by the rules, saying that on the few occasions he received requests to remove content from copyright holders, he complied.
"Copyright is an important institution, serving a beneficial moral and economic purpose," Mr Wales wrote.
"But that does not mean that copyright can or should be unlimited.
It is the latest move by Mr Wales into a political arena.
Earlier this year Wikipedia blacked out the English language version of its website in protest at anti-piracy laws being considered by the US government.
Supporters include the film and music industry, which often sees its products sold illegally. They say the legislation is needed to protect intellectual property and jobs.
Julia O'Dwyer, Richard's mother, said Mr Wales's intervention was a huge boost to their campaign.
"It is obviously quite significant to have Jimmy Wales's support," she said.
"He didn't do that lightly. He spent a lot of time talking to Richard."
She said Mr O'Dwyer was due to have an appeal heard at the High Court in October or November this year.
Mr O'Dwyer is one of several high-profile cases of Britons being extradited to the US under a treaty signed in 2003, which critics say is unfairly biased against British citizens.
He told The Guardian that he was coping "quite well" with the threat of extradition.
"It does get in the way, it distracts you... if you thought about extradition all day you'd never get any work done. It'd be a horrible mess," he told the newspaper.
"It's quite difficult but I think I'm managing quite well.
"I think about it sometimes during the day, but I try to think about other things that are more important. I don't let their extradition warrant ruin my life.
"Otherwise you'd fail university, just sit in your room all day moaning. They'd be winning if I let it do that."
A Home Office spokesman said: "We have effective, fair and balanced extradition arrangements with the US and other international partners.
"People who have committed serious offences such as murder, rape, other sex crimes and fraud, have been successfully extradited to the UK and convicted.
"It should also be noted that our courts have refused to extradite nine people requested by the US since 2004, while US courts have not refused any of our extradition requests."