A police officer has been wrongly arrested for "lightly" smacking her misbehaving son.

The Metropolitan Police officer, who has not been named, and her husband were arrested by Surrey Police officers for smacking their teenage son.

The incident, which occurred in 2019, escalated when the officer gave her son what she described as a "light smack on the left cheek" after misbehaving.

The couple, who have three children, sued Surrey Police, arguing their detention was unlawful and unnecessary.

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The couple, who have three children, sued Surrey Police

They had their claims dismissed following a civil trial last year and have since appealed against the decision in the High Court.

In a ruling on Monday, Mr Justice Bourne overturned the decision.

Bourne said: "In my judgement, on a proper analysis of the evidence at trial, the police did not show that there was an objective basis for the belief that it was necessary to arrest either claimant."

The judge said that at the time, the couple's son, referred to as ABD, had "an unfortunate history of challenging behaviour" and had started attending a youth centre to access mental health services.

The couple cancelled ABD's birthday party, leading to him misbehaving and "kicking things around".

This led to the mother smacking her son while his father was asleep, which she said "was not hard and did not cause any injury or leave any mark".

ABD told staff at a youth centre the following day that he had been assaulted by his mother, and his father had done nothing to stop it.

Despite offering to be interviewed, both parents were arrested and detained for over seven hours.

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The police arrested the couple and detained them for over seven hours

ABD returned to the family home, with police deeming that the children were not at risk of harm from the couple.

They were told there would be no further action three days after the arrest.

Following a five-day trial at Guildford County Court, a judge dismissed their legal claims, finding that police "reasonably believed" their arrests were necessary "to protect a child or children from the person in question and to enable a prompt and effective investigation".

The couple were also ordered to pay 70 per cent of the force's legal costs.

At a hearing in London at the start of the month, barristers for the couple told the High Court that the judge "erred" by finding that the arrests were "objectively reasonable".

Bourne said: "In the present case, no reason has been identified which actually explains why voluntary interviews were not a viable alternative.

"None of this means that police officers are entitled to special treatment when they find themselves suspected of an offence.

"But the police must assess the circumstances and make rational decisions as to whether coercive measures are needed or not. Merely referring to the need to protect children and to protect the integrity of the investigation was not and is not enough. It follows that the arrests were unlawful and the claims should have succeeded."