On paper, this idea seems like it would work. Allowing people to drive about to patrol roads. However, there is a couple issues with this idea:
1) The time and resources
The time and resources it would take TruckersMP to setup a whole new role and create perms, tag colour, moderation panel ect is too great for the reward they would be earning. Then you also have to get these people in police cars (that would have to be different to the moderator police car) on these roads whenever they are busy.
2) The moderation team already does a great job at what they do
Even if these roads are not being watched 24/7 by moderators, the TMP moderation team are great at their job. The issue isn't there isn't enough of them or they are only watching the CD road, it's there is too much trouble on other roads, meaning their focus needs to be on that. The mountain road is probably a second to the CD, but the amount of people on the mountain road is nothing when you look at how busy the CD really is. Also, more experienced drivers mostly are on that road meaning the amount of moderation work that would actually have to go into it is less.
3) The same issues would still occur
You can't prevent someone crashing into you by kicking them beforehand, as before that they didn't do anything. You're still going to have blockers, trollers and exploiters even if the police team where added. Adding more positions of power doesn't remove the amount of reckless behaviour on the roads, it just increases the chances of being punished for breaking TruckersMP rules. It's sort of like adding more lanes to a motorway, it doesn't reduce the amount of traffic, it increases it.