Police have given a convicted sex offender a lie detector test following concerns about his behaviour in the community.
Essex Police has become one of only four forces in the country to use polygraph testing to help manage the risk posed by convicted sex offenders.
Two officers have completed a course to become trained polygraph examiners.
In one case, detectives referred a man with previous convictions for indecent exposure for testing after monitoring visits and intelligence gathered gave rise to concerns.
He consented to the test and when quizzed about the results he admitted he had reoffended.
Officers then secured a sexual harm prevention order (SHPO) through the courts which included a condition that he must submit to a polygraph test when requested by police.
If he refuses it will be a breach of the order and he will be arrested, interviewed and could face the courts.
Detective Chief Inspector Jim Sandford said: "We use the polygraph test to get information about whether or not a sex offender is reoffending, so that we can assess the risk they pose to the public and ensure they are complying with sexual harm prevention orders imposed by the courts.
"We can't force people to take part unless it forms part of a court order and the results of a polygraph test can't be used as evidence in court.
"But the benefits are that it shows they are willing to engage and co-operate with the authorities, and it can prevent us relying on more intrusive methods of monitoring."
The test is carried out in three stages, with an interview, followed by the polygraph test and a post-test discussion.
"We have seen some participants tell us about reoffending during the pre-test interview and others make admissions after undergoing the polygraph," Mr Sandford said.
"We have had occasions where offenders have admitted further offences or breaches of preventative orders, which have triggered investigations that are ongoing.
"We have also seen some admit that they may have potential contact with children, which has allowed us to directly intervene and keep people safe."