"That is a wrong description of how things were and how things are, " he said, adding that the watchdog now had more than 380 full-time staff.

BBC: Memory stick

Your job description leads you the wrong way, and turns off candidates who could be great but are unlike you.

FORBES: Why Job Descriptions Are A Waste Of Paper

Amjad Malik QC, president of the Association of Muslim Lawyers, said the survey involved "self-description" and it was wrong to think that one in five young males in custody were "practising Muslims".

BBC: Rise in proportion of young Muslims in jail

Mistakes will happen, they'll pick the wrong person up, someone will happen to fit a crime suspect description, but the way the police conduct themselves needs to be extremely professional.

NPR: Study Focuses on NYPD Racial Profiling