[Karter2]

There may not be any specific laws to regulate towing a trailer (or another vehicle etc) in your area, but most authorities/countries have overarching laws for such things as ..."Operating a vehicle in an unsafe manner". ..
Or.....Using an illegally modified vehicle on a public highway".. Etc
(The illegal modification being fitting a non approved tow bar !!)
Just be aware , whilst there may seem to be loopholes for us to exploit, the law also has various obscure "catchall" regulations they can call on if they feel you are being a dick !

 

[Karter2]

I understand, and im pretty sure few cops would know if a Leaf was legal to tow or not, but my point was , it you catch any cop on a bad day or down on his ticket allocation, he can always find something to threaten you with.
Incidentally, down here all trailers no matter how small, must be individually registered and tested.