A committee of MPs is to examine the extradition treaty between America and the UK in light of the case of autistic British computer hacker who faces jail in the US.
The home affair select committee will consider the principal of reciprocity and whether there should be a review of the 2003 bilateral agreement.
There has been controversy over Gary McKinnon, an autistic British man wanted by the US authorities for hacking into government computer systems. He is set for deportation.
"The case of Gary McKinnon highlights the difficulties in the current extradition relationship between the UK and the US. It is clear that the US got a better deal from the extradition treaty," said home affairs select committee chairman Keith Vaz.
"The treaty needs to allow ministerial discretion in exceptional circumstances such as the case of Gary McKinnon.
"Ministers should always be able to intervene in these circumstances."
Vaz said the committee would look into the issue "in the future".
McKinnon remains in the UK as the Home Office is examining new medical evidence about his mental health.
The Supreme Court has refused to hear his case.
The Daily Telegraph reports that Conservative members of the House of Lords plan to try to amend the US/UK extradition treaty this week, "by attaching amendment to the Policing and Crime Bill which would allow prosecutors to bring charges in the UK if the crime was committed here".
Mayor of London Boris Johnson wrote to all peers last night urging them to support the amendment.
He told the Daily Mail:
"It is scandalous that under the current laws the UK has so little influence over extradition.
"There are a number of serious flaws in the Extradition Act in its current form. As we have seen with the case of Gary McKinnon.
"It can be a blunt and brutal law.
"Gary's appalling situation is just one high profile case we are aware of, but a number of other UK citizens are also in similar positions and are currently awaiting their fate."
Mental health and disability charities have spoken out against McKinnon's extradition.
He has a form of autism called Asperger Syndrome, which means that he sometimes has difficulties making sense of the outside world and communicating with others.
This makes him potentially vulnerable if he is placed in an unfamiliar environment, such as prison.

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