Years ago I actually saw one of their units, had a real medallion number on the top and everything, otherwise indistinguishable from a yellow cab EXCEPT for the four very serious individuals sitting straight up inside, and no partition (not all cabs have a partition, particularly individual medallions, which have a second letter that is in the range of A through F).
There are at least 13,000 yellow cabs in NYC, I would not at all be surprised if NYPD had several units. Great way to hide in plain sight.
Speeding enforcement? Really? Hardly ever seen it, maybe on the highways. They mostly write cell phone tickets- last two crackdowns for a single day resulted in approximately 6,882 tickets being written IN A SINGLE DAY.
And yet you still see people talking on handhelds while driving. . . trust me. . this town, while it ain't Paris or London in terms of traffic complexity, requires both hands and a brain.
I remember my first high-performance driving clinic at Jefferson Circuit-- high-speed lane change, threshold braking, slalom, going between narrowly spaced cones. . aced them all and the instructor said, "have you done this before?" "No but I do drive in New York City. . . ."