All-party committee of MPs is to question the Home Secretary Alan Johnson over his decision to extradite Gary McKinnon to America.
Gary McKinnon, a British citizen, is accused of hacking US military and NASA space agency computers.
If convicted, Gary McKinnon could spend 60 years in jail for hacking computers.
According to Gary McKinnon, he was only looking for evidence of UFOs.
All-party committee's chairman, MP Keith Vaz, said, "When considering this Treaty, the principal of reciprocity has long been contentious. I support calls for a review of this treaty in order to get the best deal for UK citizens."
The committee wants to know how the treaty between the UK and the US is used.
In addition, London mayor Boris Johnson has written to all peers urging them to vote to modify the law so that the 'blunt and brutal' extraditions like that of Gary McKinnon could be prevented.