ORG: Mobile filters censor innocent content
Pornography filters on mobile phones are "censoring" normal web content, according to the Open Rights Group.
Its report found that 60 websites were incorrectly blocked by mobile filters designed to prevent children viewing adult content.
The affected sites included political commentaries, personal blogs and community websites.
The government is considering whether to apply similar blocks to fixed-line broadband services.
Peter Bradwell of the Open Rights Group, author of the report, said the study proved such tools were ineffective.
"Child protection filters can actually affect many more users than intended and block many more sites than they should. These blunt blocks effectively add up to a system of censorship across UK networks," he said.
In a response published on the ORG website, Hamish MacLeod, chairman of the Mobile Broadband Group, denied this.
"Even allowing for the ORG missing a few, 60 misclassified websites does not amount to anything that could reasonably be described as 'censorship', particularly when mobile operators are happy to remove the filters when customers show they are over 18 and will re-classify websites when misclassifications are pointed out to them," he said.
"This is how the small handful of websites that get referred to mobile operators each year are already dealt with," he added.
In 2004, the UK's mobile operators, under the auspices of the Mobile Broadband Group, published a code of practice about how to offer a safe browsing experience for children.
At that time, few children accessed the internet via mobiles.
The result was that filters were automatically put on all pay-as-you-go handsets, regardless of the age of the user. In order to remove the filters, users needed either to ring up customer services or go into a mobile shop with proof of age. With its contract phones, Orange and Three customers need to ask if they want filters put on the handsets.
A group of MPs led by Conservative Claire Perry is campaigning to introduce similar filters to fixed line broadband services.
Mr Bradwell called on the government to reject automatic network filtering and instead give parents the option of whether they want such filters turned on.
"Default-on blocks can have significant harmful and unintended consequences for everybody's access to information," he said.