Sir Menzies Campbell warns against human rights changes
Former Liberal Democrat leader Sir Menzies Campbell has warned the prime minister against "watering down" the UK's commitment to human rights.
He spoke after David Cameron said, in the wake of riots, he wanted to tackle the "growing sense that individual rights come before anything else".
But Mr Campbell said the European Convention on Human Rights is "something we should not depart from".
Many Conservative MPs want to see the Human Rights Act repealed.
The legislation introduced into British law the principles of the 1950 European Convention on Human Rights, and was aimed at allowing people to claim the rights enshrined in the Convention without having to go to the European Court of Human Rights in Strasbourg.
In another area of disagreement between the coalition partners, Sir Menzies, a former Lib Dem leader, said: "The European Convention on Human Rights was one of the most important contributions which Britain made to post-War Europe.
"It should lie right at the very heart of our constitutional circumstances," he told BBC News.
"My view is that the ECHR is a fundamental right and that is something we should not depart from.
"I do not want in any sense Britain's commitment to the whole notion of human rights to be watered down."
Mr Cameron wrote in the Sunday Express about the need to not just "reclaim our streets, we need to reclaim our society" in the aftermath of riots in England.
"The greed and thuggery we saw during the riots did not come out of nowhere. There are deep problems in our society that have been growing for a long time: a decline in responsibility, a rise in selfishness, a growing sense that individual rights come before anything else.
"The British people have fought and died for people's rights to freedom and dignity but they did not fight so that people did not have to take full responsibility for their actions.
"So though it won't be easy, though it will mean taking on parts of the establishment, I am determined we get a grip on the misrepresentation of human rights."
Mr Cameron bemoaned the culture that has led to the "twisting and misrepresenting of human rights".
The coalition set up a commission earlier this year to examine a possible British Bill of Rights.
The commission, chaired by retired senior civil servant Sir Leigh Lewis, will report to Justice Secretary Ken Clarke and Deputy Prime Minister Nick Clegg.
It was set up to investigate a British Bill of Rights, which would incorporate and build on the UK's obligations under the European Convention on Human Rights.