TexasCHLforum.com

To the best of my knowledge, there is no state law on this subject. I have been told it is in the federal DOT Motor Carrier Safety Regulations, but no one has ever shown me a copy of it. Since I have found where the sfaety regs prohibit things like radar detectors in trucks but cannot find this, I can only assume that this is an old urban legend. It may be a carry over from the days before CHL when people thought of trucks as interstate and the carrying of a weapon across state lines was plainly illegal (other than in luggage).

My suggestion would be to write to the DPS and ask them for the legal citation. If it exists, they would know.