I do not wish to become embroiled in the question of whether or not you should, based on other than legal reasons, have one or not but feel it necessary to clarify the legislative issue. Nearly all of the requirements information published by braking system manufactures and often referenced in discussions apply to trailers, not towed motor vehicles. Although some people claim that anything towed behind an RV is a "trailer" that is not the case. The legal definitions are different.
A few years ago I did extensive research on this issue, including fully reading the applicable laws for all states that had them accessible online. In most states a towed motor vehicle does not meet the statutory definition of "trailer". At that time I found only eight states or Canadian provinces including Alaska, Florida, Nevada, North and South Carolina, South Dakota, Washington and Wisconsin that had weight-based requirements. Several other states including California have performance-based requirements defined as the ability to stop within a specified distance from a specified speed.
Know and obey the applicable laws and do whatever you feel is appropriate otherwise.
