The UK has damaged fundamental human rights by trying to undermine the ban on torture and the independence of judges, says Amnesty International.
Tony Blair says the justice system is "distant" from the public
The group's annual report attacks the government for trying to deport terror suspects to nations which use torture.
And it welcomes a Lords ruling that evidence that might have been obtained by torture cannot be used in UK courts.
Amnesty's Irene Khan said, of using torture to fight terrorism: "You cannot extinguish fire with petrol."
The governments says it does not use evidence it knows or suspects has been obtained through torture overseas.
But Amnesty fought a court battle last year over how far the government must go to show improper methods had not been used.
Kate Allen, Amnesty's UK director, said the world's leading democracies would surrender the moral high ground if they entertained the use of torture or "outsourced" torture as the Americans were doing.
Amnesty director Ms Khan attacked the UK for signing deals with countries such as Jordan, Libya and Lebanon to deport terror suspects without fear they would be tortured or killed.
She asked people to look at the human rights records of such countries and decide "whether these diplomatic assurances are worth the paper they are written on".
Amnesty is pressing the US to close the Guantanamo Bay detention camp and reveal the details of its secret prison camps elsewhere.
It also wants European Union nations to do more to investigate claims that the CIA is flying suspects through their airspace to countries where they could be tortured.
The Amnesty report, which covers 150 countries, attacks the "duplicity and double speak" of the war against terror.
The campaign is also proving a distraction from key human rights abuses, it claims.
In its verdict on the UK, the report says: "The government continued to erode fundamental human rights, the rule of law and the independence of the judiciary, including by persisting with attempts to undermine the ban on torture at home and abroad..."
Ministers have also tried to introduce measures which are odds with human rights law at home and internationally, it says.
Counter-terror measures led to serious human rights violations, it argues, and there was widespread concern about the impact of these measures on Muslims and other minority communities.
The report also says the UK has broken human rights laws through its role in detaining 10,000 people without charge in Iraq.
UK officials sat with US and Iraqi officials on the boards which review the cases of all those interned by multi-national forces in Iraq.
Amnesty says most of the people are detained by US troops but at the end of October the UK was itself holding 33 "security internees" without charge or trial.
The prime minister last week called for a "profound rebalancing" of the criminal justice system, saying it was currently "distant" from the public.
Ministers have suggested they could reform the Human Rights Act, which came into force in 2000.
Ms Khan praised the act and said there was no split between the human rights of the individual and the rights of the public at large.
"We believe the prime minister is actually diverting attention from other issues by bringing this kind of a debate into human rights," she said.
In the wake of the controversy over foreign prisoners being released without being considered for deportation, Ms Khan urged people not to give the impression that all immigrants had criminal records.
"We fear that the immigration debate is too often polarised, is exploited by governments and other political parties for short term political gain," she said.
The prime minister's official spokesman said Downing Street had not seen the report and would not give a "knee-jerk" response.
He said the Human Rights Act was an important piece of legislation.
"But we do have problems with issues like deportations that other countries do not have," he said.
"We cannot have a partial view, we cannot say the rights of the individual can take precedence over the rights of the community."
On Iraq, the spokesman said Mr Blair had seen on this week's visit to Baghdad how free elections had produced a national unity government representing all Iraqi people.
Liberal Democrat foreign affairs spokesman Michael Moore MP said the report exposed the "selectivity, faltering progress and inconsistency of our approach to human rights".