Dear Secretary Chao: 

We write to you today in support of the American Trucking Associations' (ATA) petition for determination of preemption of California meal and rest break rules (Docket No. FMCSA 2018-0304). National uniformity in the rules and regulation governing the movement of interstate commerce is crucial to ensuring the safety of our nation's roads, bridges and motoring public. 

As you are aware, commercial motor vehicles operating in interstate commerce must adhere to the U.S. Department of Transportation's (DOT) federal hours of service rules. These rules ensure a uniform set of rules for commercial motor vehicles operating across all states, taking into account commercial driver-specific highway safety evidence and fatigue science. However, running in direct conflict with DOT authority over safety and interstate commerce, California has imposed state meal and rest break laws on interstate motor carriers, creating a dangerous and confusing two-tiered system of rules conflicting with the existing uniform federal standard.