A police officer who started a sexual relationship with a vulnerable woman after arresting her for drink-driving has been jailed for 12 months.

Michael Luckett, 32, ignored warnings from his supervisor not to talk to the 30-year-old suspect after she messaged him on Facebook, his employers said in a statement.

He then kept their relationship secret while he was still a key witness in her court case.

Luckett, who served with Cheshire Police in Warrington, eventually admitted his conduct to a Police Federation representative shortly after the woman was given a 20-month driving ban.

He later pleaded guilty to misconduct in public office and resigned from his post with Cheshire Police before he could be sacked. On Friday Luckett was sentenced at Manchester Crown Court to 12 months behind bars.

“His personal behaviour was totally inappropriate for a serving police officer,” said Cheshire Police’s deputy head of professional standards, Alison Ross.

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“As a serving officer, Luckett held a position of trust and swore an oath in which he promised to abide by the clear guidelines about the standards expected from him.

“Sadly, despite the fact that he was well aware of these standards, he chose to ignore them and engaged in a sexual relationship with a vulnerable woman in a case he was supposed to be managing.

“While Luckett pleaded guilty and has now resigned from the force, that does not in any way excuse his behaviour and I hope that the outcome of this case reassures the public by demonstrating that nobody is above the law, no matter what position they hold.”

The court heard how Luckett first met the woman on 19 January 2019 after she was involved in a collision on Old Liverpool Road, Warrington. He arrested her at the scene when she failed a roadside breath test.

After she was charged with drink-driving, Luckett was assigned as the officer in charge of the case against her.

Five weeks later he told his supervisor that they had had a 30-minute conversation after she messaged him on Facebook and the case was assigned to another officer.

The supervisor told Luckett to block her and he was given formal management advice not to engage in any contact.

However it emerged that he unblocked her on 4 March and began a sexual relationship with her before her case had concluded.

Deputy Chief Constable Julie Cooke said: “It is essential that the people of Cheshire have both confidence and trust in the service we deliver.​