Williams and her husband and Portuguese sprinter Ricardo dos Santos were handcuffed in front of their infant child in July in London, leading the reigning European 4x100 metres relay champion to take to social media, where she published a video of the ordeal.

At the time, Williams called for Met Police Commissioner Cressida Dick to resign and said she was planning to take her concerns "down the legal route".

The Independent Office for Police Conduct (IOPC) are now investigating the five officers after seeing further evidence that could suggest misconduct.

"Having analysed a range of evidence including body worn, dashcam video and witness statements, we now have a fuller picture of the officers' interactions with the couple and their child," said IOPC regional director Sal Naseem.

"It is important to note that a misconduct investigation does not necessarily mean misconduct proceedings will follow.

"Decisions on any further action will only be made once our investigation is complete."

In July shortly after the incident, Dick apologised to Williams and also said the IOPC would review the use of handcuffing.

Police alleged that the car had driven away from officers after Dos Santos had allegedly been on the wrong side of the road, a claim denied by Williams.

In a statement, Dos Santos said: "This investigation has been derailed. 

"After three months we are finally told by the IOPC that the officers are being investigated for lack of courtesy.

“Polite racism is still racism - the IOPC have let the Met off the hook.

“The officer who dragged me out of the car with a raised baton and handcuffed me, who detained me under section 23 [of the] Misuse of Drugs Act and recorded falsely on my stop and search form that I smelt of cannabis is being investigated for politeness.

“How is racism ever going to be tackled in police forces if the police watchdog classify it as a ‘respect and courtesy’ issue rather than an ‘honesty and integrity’ issue. Neither the police or the IOPC seem to take discrimination issues seriously."

Williams said she is considering legal action against the Met Police and had been "shaken" by the incident.

Stop-and-search can be carried out by police in the United Kingdom under "reasonable grounds", including suspicion of possession of illegal drugs, a weapon, stolen property and items that can be used to cause a crime.

Critics of the practice say that it is discriminatory on the basis of appearance, with many arguing it unfavourably targets black people.

In one month alone, from May 8, 200 black boys and men in London between the age of 15 and 24 were stopped and searched without any weapons, stolen goods or drugs being found - totalling around 10 per cent of the city's young black males, according to statistics from the Metropolitan Police.