The use by three heavyweight European powers of information from secret services in countries that routinely rely on torture was damaging the reputation of the entire European Union, said the rights group.
"Berlin, Paris and London should be working to eradicate torture, not relying on foreign torture intelligence," said Judith Sunderland, Western Europe researcher for HRW.
"Taking information from torturers is illegal and just plain wrong."
The report, entitled "No Questions Asked: Intelligence Cooperation with Countries that Torture," found that , "The actual practices of these leading EU states contradict the EU's anti-torture guidelines, which make eradicating torture and ill-treatment a priority in its relations with other countries.”
The use of such intelligence obtained under questionable circumstances "damages the credibility of the European Union," added HRW.
Intelligence services in the three countries lack detailed instructions on how to assess and respond to information from countries that torture, said the rights group.
Torture-tainted information has been used in criminal proceedings in France and Germany, despite domestic and international rules banning the use of such evidence in proceedings, said HRW.
"France, Germany, and the UK can engage in necessary intelligence cooperation without undermining the global torture ban," said the rights group.
"To do so, they must make genuine inquiries of countries that provide information to determine whether torture was used to obtain it."