Two black men were stopped and searched by Met Police officers on suspicion of exchanging drugs because they had bumped fists, a watchdog has found.
The Independent Office for Police Conduct (IOPC) reviewed the Met’s use of stop-and-search powers.
IOPC director Sal Naseem said the “legitimacy of stop and searches was undermined” by a number of issues.
The Met said stop-and-search was a “vital and legitimate power that protects Londoners”.
In one investigation, a black man in possession of someone else’s credit card was suspected of having stolen it even after providing a credible explanation, the IOPC said.
Met officers exercised stop-and search-powers on another occasion after two black men fist-bumped, as they suspected them to be exchanging drugs, the review found.
In two investigations, the smell of cannabis formed the sole grounds given for a stop, according to the watchdog.
It also highlighted the failure of officers to use bodycam video from the outset and to seek further evidence after initial grounds for the stop-and-search were unfounded.
Several investigations found although an initial search was negative, officers were slow in ending the encounter.
Mr Naseem said the findings “mirror concerns expressed to us by communities across London” and 11 recommendations from the review had been made and accepted by the Met.
“We saw a lack of understanding from officers about why their actions were perceived to be discriminatory,” he added.
Recommendations include offering better education of powers to officers, ensuring racial prejudice is removed and making sure the stop and search encounter is ended swiftly after suspicion is allayed.
Mr Naseem said: “We recommended [the Met] takes steps to ensure that assumptions, stereotypes and bias (conscious or unconscious) are not informing or affecting their officers’ decision-making on stop and search.
“There is also a need to better support officers on the front line to do their jobs effectively with the right training and supervision so they aren’t subjected to further complaints and investigation.
“There is clearly much room for improvement.”
A Met spokesman said: “We recognise that how the tactic is approached, trained and delivered, remains a significant area of concern for communities across the capital and we are committed to ensuring that every encounter is conducted professionally with respect and courtesy.
“We understand the impact that even a thoroughly professional encounter can have on an individual stopped and searched, and that its impact can resonate more widely with communities.”