More than 50 drivers were stopped in Maple Cross as part of a major police crackdown on drivers breaking the law.
Hertfordshire Constabulary teamed up with the Metropolitan Police using number plate recognition cameras in Denham Way to identify motorists who did not have any insurance, were driving while on the phone and operating vehicles unfit for road use.
Officers stopped and checked more than 50 vehicles on Friday, May 23 between 4pm and 8pm.
Action was taken against 31 drivers who were given a £60 fixed penalty notice for not wearing their seat belt or using a mobile phone whilst driving.
One vehicle was seized for having no insurance and five more were found to be defective and received notice to repair them.
All the vehicles were flagged up on the Automatic Number Plate Reader (ANPR) system.
Police Constable Christian Gottman led the operation and said: "We regularly carry out these operations with our colleagues in neighbouring police forces and they are a useful tool to deter any potential offenders planning to commit crime, such as burglary and other acquisitive crime, in Three Rivers.
"Experience with ANPR has revealed very strong links between the use of motor vehicles on the road and criminality so it is a great tool to detect and remove serious criminals including burglars, robbers, drug dealers and fraudsters - and unsafe vehicles and unsafe drivers from the roads.
"We will continue to work closely with our neighbouring forces, using all the tools we have to prevent crime and deny criminals the use of the roads."