The Conservatives brought a motion asking for the government to review the Extradition Act 2003 which it said was being undermined by a series of high profile cases that harmed confidence in the extradition system.
McKinnon (43), from north London, was arrested in 2002 on suspicion of hacking US government computers in 2001. The US did not ask for his extradition until the 2003 Act came into force.
McKinnon is appealing against the decision of the director of public prosecutions (DPP) not to try him in the UK. The DPP said earlier the UK lacked the evidence to bring a prosecution against McKinnon, and that therefore the trial should take place in the US.
If convicted, McKinnon, who suffers from Asperger's syndrome, faces up to 60 years in a maximum security prison.