The Met Police has published footage of officers knocking suspected criminals off scooters, at the same time as the watchdog is investigating some crashes.
Videos released by the force show police cars being driven into riders.
The Met says it has cut scooter crime by 36% this year.
However, the Independent Office for Police Conduct (IOPC) said it is investigating three cases involving "tactical contact" by Met police cars on scooters.
The number of offences involving scooters has fallen since specialists teams were set up to tackle the problem.
In January 2018 to October 2018 there were 12,419 offences, 7,036 fewer than the same period in 2017.
The Met says drivers are specially trained and aim to end pursuits before riders or members of the public are injured.
A spokesperson said the tactic is not new but is being used more often by its most highly trained drivers working on Operation Venice; the team set up to tackle scooter gangs.
According to the IOPC, one of the cases being investigated involved a 17-year-old boy who suffered head injuries a year ago in Bexley.
However, none of the three cases involved officers involved with Operation Venice.
Met Police Commander Amanda Pearson said "a lot of them [scooter riders] get up and run away and look aghast as if to say 'how dare we'".
She added: "It's a high impact tactic and therefore our riders and our drivers will be considering the risk to the rider that they are pursuing, the risk to the public and the risk to themselves.
"But in more cases than not it is safer to bring that pursuit to a close than it is to continue to allow that rider driving dangerously through London."