In the two months following their introduction the force reported that anti-social behaviour arrests have risen by 85 per cent, detection rates are up 40 per cent and violent crime has fallen by eight per cent.
Over 200 officers are now equipped with the cameras.
"The figures show what a significant effect the head cameras have had in reducing violent crime," Chief Superintendent Morris Watts of Devon and Cornwall Police told The Mirror.
"They are being used to record a range of crimes, providing the courts with hard evidence. People are now aware they are being filmed and, given these factors, this success could just be the tip of the iceberg."
The £1,800 cameras record the operator's view and store the data on a belt-mounted hard drive. Each drive can hold 400 hours of footage.
Evidence collected by Devon and Cornwall Police included a riot in Plymouth, drunken abuse directed at an officer and cases of disorderly conduct and public urination.
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