Gary McKinnon: Mother urges President Obama to pardon son
14 December 2012 Last updated at 16:08 GMT
Computer hacker Gary McKinnon, who is wanted in the US, will not face charges in the UK, the Crown Prosecution Service has said.
Director of Public Prosecutions Keir Starmer QC said the chances of a successful conviction were "not high".
He announced the decision some three months after Home Secretary Theresa May stopped the extradition.
Mr McKinnon, 46, admits accessing US government computers but says he was looking for evidence of UFOs.
His mother Janis Sharp said the news came as a great relief.