This came off Mississippi dept of taxation web site. When I bought my boat in 2010 I was given a paper, actual law as written in books stating same thing. Doesn't mean they won't write you a ticket though.
Does Mississippi title boats, watercraft and boat trailers?
Please contact the Mississippi Department of Wildlife, Fisheries and Parks (phone 601-432-2065) for information on boat and watercraft registration requirements in Mississippi.
Boat trailers may be voluntarily titled if less than 5000 pounds Gross Vehicle Weight (GVW.) If the trailer is over 5000 pounds GVW, then it is required to be titled
Title Frequently Asked Questions
(Psalms 39:7) "And now, Lord, what wait I for? my hope is in thee."