The Government has been under mounting pressure to reform its "one-sided" extradition laws after a student and a businessman lost their battles to avoid criminal trials in the United States.
Richard O'Dwyer, 23, would be the first British citizen to be extradited over the illegal streaming of films and would effectively become a "guinea pig" for copyright law in the US, his lawyer said.
O'Dwyer's mother Julia warned there were no safeguards for Britons and accused the UK of "pandering to the US" as campaigners called for the Government to reform extradition laws in the Queen's Speech later this year.
The call came as retired businessman Christopher Tappin vowed to fight on to end his "nightmare" after failing in a High Court bid to halt his extradition to the US on charges of conspiring to sell batteries for Iranian missiles.
An independent review of the UK's extradition arrangements by Sir Scott Baker last year found the current treaty between the US and the UK was both balanced and fair.
But the Government is under pressure to ignore its findings after MPs called on ministers to bring forward new laws and attempt to change the UK-US extradition treaty and European Arrest Warrant regime.
The review, which angered campaigners, contradicted the findings of the Joint Committee on Human Rights, which called for the Government to renegotiate the UK's extradition treaty with the US to ensure British citizens get the same protection as Americans.
Mrs O'Dwyer, from Chesterfield, Derbyshire, said: "If they want to prosecute something they will. There's no safeguards here for British citizens."
Her son, an undergraduate at Sheffield Hallam University, allegedly earned thousands of pounds through advertising after he created a website which helped people watch films and TV shows for free.
But the TVShack site was closed down by the US authorities and he faces jail if convicted of the allegations, which were brought following a crackdown by the US Immigration and Customs Enforcement agency.