Jeffrey Howard Davies, a family liaison police officer who preyed on two domestic violence victims to get his sexual kicks, has been jailed for three years.
Swansea Crown Court judge Paul Thomas told the disgraced 42-year-old former officer he should expect a tough time in prison.
Davies, who worked for South Wales Police, touched a distressed woman and tried to get another to touch his groin.
The women say they now live in fear of the police - with one suffering panic attacks following her ordeal.
"The sexual assaults you perpetrated on these women were a gross betrayal of your position as a police officer.
"When a serving police officer behaves in the way you did, it has a huge impact on the way the public view the police. It makes the task the police face even harder than it already is.
"It is true, that no one despises a rogue policeman more than his former colleagues.
"You took advantage and preyed upon vulnerable women for your own sexual ends.
"You targeted them as you viewed them as women who would obviously not have the confidence to complain or be believed if they did.
"Even if these women had agreed to have sexual relations with you, it still would have been a serious matter.
"You have not showed even a scintilla of remorse.
"Prison will prove difficult due to your status as a former police officer, but my ultimate duty is to redress the public's confidence in the integrity of the legal system."
Defending barrister Lucy Crowther said her client had accepted there was limited mitigation that could be made given his not guilty plea, which a judge said had put the victims through even more stress.
She had tried to argue that, in some respects, the extent of Davies' sexual relations had not been as serious as two police officers who had been convicted of having sex while on duty.
Former Greater Manchester Police officer Michael Fletcher was jailed for 32 months in 2011 after having penetrative sex with a vulnerable adult while on duty.
And ex-Avon and Somerset Officer Kenny Lewis, 26, was jailed for four years in 2009 after engaging in sexual activity with a number of "vulnerable" women, also while on duty.
Ms Crowther asked the court to impose a sentence nearer the sentencing guidelines for an offence of sexual touching - which has a lower starting point.
However, while Judge Thomas acknowledged that Davies had not engaged in "more intimate" sexual activity, he argued that there was a key difference in the case.
"The sentencing guidelines, if you excuse my inelegant phrase, fly straight out of the window," he said.
He pointed out that the sexual activity engaged in by Davies, although of a less serious nature than in the Fletcher and
Lewis cases, had no consent whatsoever.
He added: "A long prison sentence must follow."
As well as imposing a three-year custodial term, Davies was placed on the sex offenders register indefinitely.
Wearing a blue and red checked shirt and trousers, he bowed his head in shame as he was taken down by two security guards.
Throughout the hearing, the disgraced officer could also not bring himself to look towards the public gallery where several of his former colleagues sat.
South Wales Police's Assistant Chief Constable Richard Lewis said now that sentence had been passed, gross
misconduct proceedings against Davies would be taken forward.
He added: "His actions were a gross abuse of position and power which will not be tolerated within policing.
"The thorough and determined investigation carried out by South Wales Police and managed by the IPCC, demonstrates our determination to tackle behaviour of this kind."