The Open Rights Group has slammed Ofcom's draft Code of Practice to tackle net piracy, claiming the code fails to outline the standard of evidence needed to prosecute those accused of illegal file-sharing.

The watchdog published the draft code of practice last month, in a bid to fulfil the measures to tackle internet piracy set out in the Digital Economy Act, which became law earlier this year.

Under the code, which initially applies only to fixed-line ISPs with more than 400,000 subscribers, ISPs will have to send warning letters to web users suspected of illegal file-sharing. The details of those that have received three or more notifications in a year can be requested by copyright holders in a bid to start legal action.

However, Jim Killock, executive director of the Open Rights Group, said the code did not outline the requirements for the standard of evidence needed to start legal action, or how it should be obtained.

"Ofcom's proposal denies us the ability to check whether any of the evidence is trustworthy. Instead, copyright holders and internet service providers will just self-certify that everything's okay. If they get it wrong, there's no penalty," said Killock.

"The act requires the evidential standards to be define. But Ofcom has passed the buck. How is anyone meant to trust this code if we can't see how the evidence is gathered or checked?"

He also said the code fails to fulfil requirements in the Digital Economy Act that require Ofcom, not ISPs or anyone else, to reduce illegal downloading in the UK.

Killock referred to letters issued by Gallant Macmillan on behalf of the Ministry of Sound this week, accusing the recipient of illegal file-sharing and asking for a compensation of payment or run the risk of facing legal action.

"We know things go wrong, and that's why the act requires the evidential standards to be set out," said Killock.

"What we need now is a new consultation on a new code that is compliant with the act."

Ofcom's consultation period on the draft code of practice is due to end on July 30. However, it looks unlikely the watchdog will amend the code.