Police say new powers allowing them to test criminals for drugs is helping to reduce crime.
Stafford and Cannock police officers have been given powers to test people charged with certain crimes such as burglary and car crime so they can be offered treatment.
A police spokesman said figures showed 45% of tests were positive.
The worst area was Hackney with 66% and the area with the lowest percentage of offenders who tested positive for drugs was Torquay with 36%.
Sergeant Russ Cartlidge said the tests are helping to break the link between drugs and crime.
“The scheme is twofold because we are able to get offenders the drug treatment they need,” he said.
“In doing so, we’re reducing the need for crime to be committed to finance an illegal drug habit.”
The new drug testing powers are being introduced to 30 areas identified as being the worst affected by drugs-related crime.