Ed Miliband has said the Tory's plans to scrap the Human Rights Act for a Bill of Rights would be a "disaster" for the gay, elderly and disabled people of Britain.
The Labour leader said the current human rights laws, imposed by the Labour Government, have protected vulnerable people such as victims of crime for years and Britain should not "put that at risk".
Justice Secretary Chris Grayling announced if the Conservatives win next year's general election they will impose a drastic revamp of the current laws and pull out of the European Courts of Humans Rights (ECHR).
Under the new proposals, the Human Rights Act would only be used in the most "serious cases" and will prevent suspected foreign criminals from using it in order to fight off deportation.
The Bill of Rights would also mean Britain would not have to consult with the Strasburg courts before making any decisions.
Miliband said pulling out of the ECHR would put Britain on par with Belarus, the only country left in Europe run by a dictatorship.
In a post on Facebook, Miliband said: "Our human rights laws have protected the rights of victims of crime, the elderly, the disabled and gay people. We shouldn't put that at risk.
"Labour has called for reform of the European Court of Human Rights. We think Strasbourg needs to do more to improve the quality of judges and give countries room to interpret decisions appropriately.
"But leaving the European Court of Human Rights, which the Tories appear to be proposing, would be a disaster for this country – putting Britain in the same bracket as Belarus."
Civil rights groups also compared the Conservative's proposals to that of a dictatorship.
Tim Hancock, campaigns director of Amnesty UK, said: "Under these plans human rights would be reserved for only those people the government decides should get them. This is a blueprint for human rights you would expect from a country like Belarus.
"We should all be worried when politicians try to set themselves above the law."
The Bill of Rights has also come under criticism from those connected to the Tory party. Dominic Grieve, the former attorney general, said the paper in which the proposals are written on is full of "howlers which are simply factually inaccurate".
He told BBC Radio 4 Today programme: "One howler is...where it says that the court of Human Rights in Strasbourg has prevented the imposition of whole-life tariffs on whole-life tariff prisoners in this country.
"It hasn't. Its judgment never said that."
He added: "It seems to me it is factually inaccurate in what it says, and that is unfortunate.
"If one is going to approach a complex subject, I think it is very important that we should all collectively adopt a moderate and measured approach towards explaining what the issues are and what can and cannot be done."
The proposals were also met with a negative response from members of the coalition. Simon Hughes, the Liberal Democrat justice minister, said: "The Conservatives don't care about the rights of British citizens, they care about losing to Ukip. These plans make no sense – you can't protect the human rights of Brits and pull out of the system that protects them."