Section 61-9-321 - Engine compression brake device - use(1) A commercial motor vehicle equipped with an engine compression brake device must be equipped with a muffler in good working condition to prevent excessive noise.(2) An operator of a commercial motor vehicle that has an engine compression brake device with a factory-installed muffler or an equivalent after-market muffler may not be prohibited from using the engine compression brake device.(3) The department of transportation employees who are designated as peace officers pursuant to 61-10-154 shall work with law enforcement in the enforcement of standards adopted pursuant to this section.(4) Notice of a deficiency must be given pursuant to 61-9-501.(5) A violation of the rules adopted to implement to this section is punishable as provided in 61-9-521.En. Sec. 1, Ch. 357, L. 2003; amd. Sec. 217, Ch. 542, L. 2005; amd. Sec. 1, Ch. 146, L. 2009.