Every couple of weeks a police officer in Kent is spat at, as they try to arrest a suspect, or when they're in the station.
So to protect them, Kent Police decided in June to give all their officers spit guards. They have been used by police in Sussex for many years.
They can be put over a suspect's head after they've been handcuffed - when officers are worried they might be spat at.
Kent Police's safety trainer, Adam Pilbeam, has has been showing his colleagues how - and when - to use them.
But civil liberties groups say these spit guards are cruel and degrading.
Abigail Bracken went to see how they are used at Kent Police College. She spoke to Adam Pilbeam, PC Ben Startin and Asst Ch Con Tony Blaker.