I have done some of that research.
Enough to know beyond a shadow of a doubt that the "compendium of laws" DO exist as stated, but NONE that I have seen are accurate!
I base that statement on the information given for Montana in such lists. IT IS NOT TRUE! I have done considerable research in the Montana Code Annotated 61- series, and I CAN give the references if desired.
The braking performance requirements are as nearly universal as one can get. As a Federal regulation, they apply to all states, and nearly all states have incorporated them, nearly verbatim, in their state statutes. "Nearly verbatim" because the stopping distance can vary, as in CA says 45 feet and Montana says 40 feet, from 20 MPH on a hard, level, clean dry surface.
I have never seen a "List Of Towing Laws" that is any where near accurate or complete enough to be used as a reliable reference!