A detective sergeant has been jailed for 18 months for sexual assaults on two colleagues.

Richard Mills, 42, an officer for Greater Manchester Police since 2006, was found guilty after a trial of assaulting the women while at work on two separate occasions over the past 10 years.

Sentencing him, Judge David Swinnerton said Mills had been “enabled” and “emboldened” by a culture within the lower ranks of the force of “you don’t report bobbies”.

The court heard the father-of-two, whose wife was in the public gallery of the court, described an office environment within the force where there was “sexualised banter” by a number of people.

Judge Swinnerton said witnesses during Mills’ trial spoke of the “sexual overtones” of conversations he would have with colleagues.

His first victim said he put her hand on his crotch after telling her about what kind of sex he liked and saying he was not “getting it” from his wife.

She told others about the incident but did not support an investigation into Mills at the time, so he was given a verbal warning but no misconduct hearing took place.

The judge said: “You should have learnt your lesson.”

The second complainant said she “froze” when Mills put her hand onto his crotch while in a room with other people.

“That added to her sense of shame and embarrassment that you felt enabled to do that in that room believing she would not say anything,” the judge said.

Judge Swinnerton said the women had had their “mental health, careers and their lives blighted” by what Mills had done.

He added: “When police officers commit offences like this, or any other sort of offence, you undermine every other officer because it does damage public trust in police.”

In a statement read by Robert Dudley, prosecuting, at Liverpool Crown Court on Friday, one of the victims said: “How do you call the police about the police?”

She added: “I used to be such a happy, smiley and bubbly character and I feel the complete opposite. I just feel sad all the time.”

Hunter Gray, defending, said Mills continued to deny the offences.

He said: “He will lose his job as a result of this, the disciplinary proceedings will take their course but there is an inevitability about that.

“The circumstances are very much now in the public arena, having been published, and it is extremely humiliating not just for him but for those close to him, including his wife who has attended today.”

He said Mills had shown insight into his previous conduct and was no longer “the tactile person he was”.

He added: “He would say that what he saw as acceptable banter at the time he now appreciates was unacceptable, particularly in the modern environment, and he will change his approach.”

Mills was cleared of three other counts of sexual assault following his trial.