Widespread use of torture is continuing in Turkey despite the government's "zero tolerance" policy, says human rights group Amnesty International.
Amnesty noted a fall in the incidence of torture in police custody
A new report acknowledged improvements in the Turkish criminal justice system in recent years.
But Amnesty said a "culture of impunity" allowed the authorities to escape accountability and the courts to disregard medical evidence of torture.
There has been no immediate response from the Turkish government.
The Amnesty report, published on Thursday, noted a fall in the incidence of torture in police custody.
But it also said the declared zero-tolerance policy could not be seen as effective "until real steps are taken to address the persisting issue of the failure to punish officials who violate the absolute prohibition on torture and other ill-treatment."
According to Amnesty, detainees in Turkey alleged they had been beaten, threatened with death, deprived of food, water and sleep during detention.
Some of the torture was said to have taken place in unofficial places of detention.
The head of Amnesty's programme in Europe, Nicola Duckworth, said: "Nothing short of a fully implemented policy of 'zero tolerance for impunity' will end the spectre of torture, other ill-treatment, killings and enforced disappearances which still blight Turkey's human rights record."
Turkey introduced a series of sweeping changes several years ago to the country's penal code, intended to bring Turkish laws closer to those of EU member states.
Torture was abolished and individual liberties expanded under the reforms.
Human rights are a key issue in its bid to join the EU.