Senior MPs and members of the House of Lords have warned the Government that its plans to introduce new laws to stop internet 'trolling' may have a 'chilling effect' on the right of free speech.
The Joint Committee on Human Rights, the cross-party committee that looks at all matters relating to human rights, warned that reform to libel laws could force website operators like Twitter to remove offensive content, even if that content was not in breach of the law.
The Defamation Bill, which is due to go through the committee stage in the House of Lords on 17 December, has faced considerable criticism during its passage through Parliament.
Central to much of the criticism is the argument put forward by the members of the science community, headed by Professor Brian Cox, that the bill needs to have a 'public interest' defence, in order to prevent the stifling of genuine scientific debate and criticism.
It is feared that any new law that prevents honest, but potentially unfounded, criticism of others will have a profoundly detrimental effect on science, research and development.
Baroness Jay is the chair of the House of Lords constitution committee.
"It is important that journalists and publishers feel confident that they can draw attention to matters of public interest without fear of being sued for defamation," she said.
The bill includes a defence to online defamation if the website operator facilitates communication between the claimant and the publisher of a potentially defamatory comment, but requires the website to pull content down if that communication cannot be facilitated.
The test of potentially defamatory content is whether it 'has caused or is likely to cause serious harm to reputation'. However, any publisher of such comment will, under the act, have a defence if the content proves to be 'substantially true'.
The Joint Committee believes this could have a serious effect on free speech and would like the bill to include a higher threshold for removing online content. The fear is that websites like Facebook and Twitter will simply remove potentially offensive comments to protect their own reputation, even if in the end the comments are true.
Lord Lester, a Liberal Democrat peer, wants a new defence inserted into the bill to protect anyone who acted 'honestly and reasonably believed that their statement was in the public interest'.
The Government has accused the committee of seeking to make the new law unnecessarily complicated.