“Improper Right Turn”

While attempting a right turn off of a wet ice patched highway travelling 75 km/h (posted max=90) I slowed down and moved into the right turn exit lane which was much more slippery that the travelled lane was. In the right turn lane the vehicle started to slide with the slightest brake pressure and little to no steering response (antilocks operating). The vehicle slid through the intersection sideways, hit a low snow bank and tipped over into the ditch. There were no other vehicles in the intersection and no other people involved or property damage ... except my vehicle. The police arrived and the result was a $110 ticket + 2 pts for an "improper right turn". There was no mention or comment made on the accident report of the poor road conditions. I can admit to hitting the ditch but I can't see how it could be an "improper right turn" given the conditions. Assuming that argueing with the officer in a trial court will be pointless, my thought is to plead guilty (at walk-in) and try to reduce the fine at least. Still can't believe I got points for this, or even a fine. Any advise ?