Here are a couple of female police officers training on LE Velos.
It's seems slightly strange that there are so few policewomen currently patrolling on motorcycles in the UK. I've never seen any on duty - which is not surprising, since in 2010, for example, there was only one in the entire North of England:
Special recruitment efforts have been made in the past:
A August 2015 article from the "Visor Down" website describes one Emma Poston as "the only female police motorcycle sergeant and currently the only woman running Bike Safe courses in the capital".
There were three female motorcyclists deployed by the Strathclyde force in Scotland in 2012:
Here's a policewoman motorcyclist at Brighton:
The obituary of Inspector Janet Knott can be found here-
But these are exceptions rather than the rule. It's different in other countries: