Torture by Syrian rebels: always in passing

Look how it is only mentioned in passing: "United Nations investigators said that several armed opposition groups, including the Islamic State of Iraq and Syria and the Nusra Front, had detention facilities in hospitals, schools and other public buildings in areas under their control, and that those most at risk of being held for interrogation included activists and people trying to document abuses." And notice that they always manage to identify groups that are banned by the US but never mention torture by Free Syrian Army.  I really think that the worse human rights abuses have been committed by the moderate FSA--but I dont have concrete evidence to point to.  But when it came to sectarian killings and indiscriminate shelling, the FSA is a pioneer.