Internet providers in the UK could be given powers to block user access at their own discretion in an amendment to the controversial Digital Economy Bill.

The Bill, currently being scrutinised by the House of Lords*, will introduce age verification checks for online porn. Under the proposed legislation, pornographic websites that fail to implement checks would be blocked by all UK ISPs.

But an amendment by the House of Lords published this week [PDF] appears to permit an ISP to engage in content filtering, provided that it is consistent with its terms of service. The update was written by Lord Ashton, a parliamentary under-secretary at the British government's Dept of Culture, Media and Sport.

Neil Brown, an internet, telecoms and technology lawyer, said: "If enacted as currently written, the Bill would compel blocking in some circumstances, and permit it in many more."

He said that amendment is in contrast to a separate clause for an appointed age-verification regulator to compel an ISP to take steps to prevent UK end users from being able to access the "offending material".

Under that clause, it would be the statutory duty of an ISP to comply with any such notice.

He added: "We will need to see how the amendment is characterised in the debate, and whether that gives any insight into its introduction." He said the clause may be intended to ensure that UK ISP filtering is consistent with the EU's net neutrality framework.

Concerns have been raised as to how the age verification will work in practice, and if that will require the collection and retention of documents such as a copy of passports or driving licences.

The Delegated Powers Committee in the House of Lords has also criticised the "inappropriate" and "untrammelled" citizen data-sharing powers contained within the Bill.

It recommended that the government removes broad powers to share information with a range of "specified persons", which could include private-sector bodies. ®

*Among the lords to put down a series of amendments is the Lib Dem peer Floella Benjamin (Baroness Benjamin). Readers might remember Benjamin for presenting the Beeb's Play School in the 1970s. Hat tip to reader Rich Greenhill for the spot.