There are plenty of ways to break a leg! And police officers aren't a particularly healthy group, tending to be overweight and out of shape. Combine that with a job that involves infrequent but strenuous exertion and you get lots of injuries.

I'm certain the broken leg will be discussed but it is likely that the break has nothing to do with any particular action by the deaf person.

e.g., my neighbor "broke his leg" a few months ago in the first few minutes of playing soccer with his grandchildren. No contact was required: he slipped while setting up for a kick and broke his fibula.