Third of UK police forces using controversial spit hoods
The BBC has learned that 17 of the UK's 49 police police forces use hoods to prevent arrested people spitting or biting.
They have been used at least 2,486 times since 2011; 635 of those cases were on people with suspected mental health issues.
Che Donald, of the Police Federation, said police need to take "active precautions" to protect themselves.