Thanks for the updates and for your patience.
I had to do quite a bit of reading and legal research to get to this answer, which is somewhat convoluted. The botXXXXX XXXXXne is that I think 1) you are charged under the correct statute, 2) the cops may be able to prove their case, and 3) the fine is $500.00 and not $750.00.
14-262d is entitled "Permits for vehicles transporting mobile homes, modular homes, house trailers or sectional houses." This doesn't seem to apply to you, as you simply had a trailer and you were not transporting a mobile home, etc.
The fine for a violation of this statute is "no less than $300.00." To find the fine amount, you go to 14-270, specifically to subsection (g)(3). That is the fine for trailers carrying modular homes, etc., which trailers are too long. So, the fine fits ($750 is clearly more than $300), but the statute doesn't seem to fit the facts of your case, since you were not carrying a modular home.
Now, let's look at 14-262. This is a different statute that the one listed above. Click the link in the previous sentence to read the entire statute. Subsection (d) of this statute lists a standard fine of $500.00 if this section is violated.
The portion of the statute that I believe most applies to your situation states the following:
(c) The maximum length, including load, of a single unit vehicle shall be forty-five feet and the maximum length, including load, of the semitrailer portion of a tractor-trailer unit shall be forty-eight feet. A trailer greater than forty-eight feet and less than or equal to fifty-three feet in length, that has a distance of no more than forty-three feet between the kingpin and the center of the rearmost axle with wheels in contact with the road surface, may be operated on (1) unless posted otherwise, United States and Connecticut routes numbered from 1 to 399, inclusive, 450, 476, 508, 693 and 695 and the national system of interstate and defense highways, and (2) state and local roads for up to one mile from the routes and system specified in subdivision (1) of this subsection for access to terminals, facilities for food, fuel, repair and rest, and points of loading and unloading. ...
The part that catches my eye is underlined above.
If you are charged under this section, the questions for the judge will be 1) whether the trailer you had was greater than 48 feet in length, 2) whether the distance between the kingpin and the center of the rearmost axle with wheels in contact with the road surface is forty-three feet or less, and 3) whether you were operating your rig on one of the routes NOT listed in the statute. If the answer is yes to all three questions, you will likely be found guilty.
From the facts as you've stated them, it sounds like the first two factors (overall length and kingpin to rear axle measurement) true. The only missing piece of the puzzle is the route you were allegedly driving on.
All that aside, the statute specifically states that the fine is $500.00 if this code section is violated. Frankly, I'm at a loss to explain to you where the $750.00 fine is coming from. Maybe the trooper or cop just got that wrong. Thus, even if you are convicted of this infraction, my reading of the statute is that the fine is $500, no more and no less.
Finally, yes, I agree... That's QUITE a steep fine for axle spacing. I guess we know where CT gets at least part of its state revenues from...
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