Without knowing the OP's driving history, it would be remiss to leave such things out. If he has a large number of past speeding infractions, for example, a JP might choose to make an example of him.
I've seen a JP make an example of someone - a kid charged and convicted of careless, he gave an additional 6 month licence suspension.
I'd imagine though, that a HTA 172 would automatically be heard in provincial offenses court in front of a real judge who puts people away for serious crimes - not that HTA 172 isn't serious, but it's much less serious than murder or armed robbery. A JP just doesn't exist in that realm, so I'd imagine HTA 172 would be considered a high-crime to him/her.
Anyway, make sure your representative has your charge heard in provincial offences court.