He also used the force’s database to retrieve personal details about his victims.

The married father-of-two was convicted of misconduct while in public office. He was dismissed from his job last December.

One woman was driving with only a provisional licence when Slater pulled her over.

Peter Davies, prosecuting, said: "Mr Slater told her he would have to retain and impound the motor car she was driving.

"This caused her to be upset and she began crying. It was at that point Jamie Slater told her if she would give to him her mobile number he would not cause the car to be retained. She agreed to do so."

The court heard they began a consensual affair and on one occasion the pair met for sex while Slater was on duty and he received an emergency call on the police radio.

He became involved in a high speed chase while the woman was hiding in the car.

When her husband found out about the affair Mr Slater retrieved his details from the police database and sent him taunting messages, Mr Davies said.

One victim was pulled over when she drove through a red light and gave Slater her phone number because she was scared of the consequences of refusing.

He later sent her graphic text messages.

Mr Davies said: "She was left scared and upset and said she would never get into a police vehicle again, having lost faith in the police force."

The barrister said all Mr Slater’s victims felt powerless to do anything because he was a police officer in uniform.

On another occasion, Slater pulled over a woman and told her he would impound her car for driving without insurance.

He said if she agreed to meet up with him he would see she got her car back without pay for the cost of the recovery.

Mr Davies said Slater sent her text messages asking her to wear stockings, saying he was aroused.

He later sent her messages telling her where she had been that day and what she was wearing. He also sent her a photograph of her driving her new car.

The barrister said: "She felt she was effectively being stalked. He would pull up in a patrol car outside her place of work and remain there for 20 minutes."

He sent another woman, who he pulled over for driving through a red light, messages saying: "Will you have sex with me today?"

The court also heard Slater pulled over a 19-year-old girl who was speeding on the M4 motorway and told her she could lose her licence if she was prosecuted.

He said he would let her off and asked for her mobile number.

The court heard he took her for drives in his patrol car and tried to kiss her and touch her leg.

Another of his victims was a pregnant woman Slater had never met.

He sent her a message saying: "Fancy meeting up for some sexy fun?"

He later texted her saying: "Did you used to be a working girl? How much do you charge for a f***? I want to f*** you. Will you send me a pic?"

Mr Davies said: "One day she received 35 texts with explicit requests for sex using vulgar tones."

Slater also met up with prostitutes while on duty.

Tom Crowther, mitigating, said Slater, who used to be a chartered surveyor, had always wanted to be a police officer but had suffered from depression and had financial difficulties prompting him to set up a driving school to make extra money.

Sentencing Slater, Mr Justice Lloyd Jones said he acted in "a particularly predatory manner."

He added: "Your activities have caused immense damage to the public confidence in the police."

Tom Davies, Independent Police Complaints Commissioner for Wales, said Slater was dismissed from South Wales Police in December.

He said: "Slater was a disgrace to all who work for the police service and abused the position of trust a serving police officer is given."