WASHINGTON — The U.S. Court of Appeals for the District of Columbia Circuit upheld the 34-hour restart provision of the new truck driver hours-of-service rule but rejected the 30-minute break requirement for short-haul drivers.

“[The Federal Motor Carrier Safety Administration] won the day not on the strengths of its rulemaking prowess, but through an artless war of attrition,” wrote Judge Janice Roberts Brown for the unanimous court.

In last week’s decision, the court mainly deferred to FMCSA expertise on the details.

“We conclude that what remains of the 2003 Final Rule after two remands and three rulemakings are highly technical points best left to the agency,” Brown wrote.

The court looked at arguments against the 34-hour restart rule, including its provisions limiting use to once a week and requiring drivers to take off two periods between 1 a.m. and 5 a.m.

Public Citizen had challenged the restart rule generally, but the court decided that the group did not justify its standing to make the challenge.

American Trucking Associations (ATA) had challenged the two limitations on the restart.

ATA argued that the one-a-week restriction was invalid because the agency had in the past supported unlimited use of the 34-hour restart.

But the agency said it changed its view when it learned that some carriers used the unlimited restart to add an additional work shift per week.

It is reasonable for the agency to make such a change, the court said in upholding the once-a-week limit on the restart.

ATA’s criticism of the two-night requirement was that it runs counter to the agency’s practice of promoting a consistent, 24-hour daily schedule.

The requirement that drivers take two periods off between 1 a.m. and 5 a.m. encourages night drivers who are used to sleeping during the day to get their rest at night during a restart, ATA said.

The agency’s response to this was that it never pushed maintenance of circadian rhythms above all else, and the court agreed.

Even more compelling, the court said, is a study concluding that two nights of rest are better at mitigating fatigue in nighttime drivers than one night.

The court also addressed Public Citizen’s challenge of the 11-hour driving limit.

The agency settled on the 11-hour limit because it could not show that a 10-hour limit would have higher net benefits.

Public Citizen contended that this in effect put cost-effectiveness before safety, contrary to the law.

The court said that while this argument “has some intuitive appeal” it reads too much into the law.

“We cannot say [the agency’s] approach is irreconcilable with congressional intent,” Brown wrote.

The court rejected two of ATA’s three arguments against the requirement that short-haul drivers take a 30-minute break.

But the third argument hit home. ATA said the agency did not adequately explain its decision to apply the break requirement to short-haul drivers as well as long-haul drivers.

The court agreed, and said that the 30-minute break requirement for short-haul drivers must be vacated.

The court also addressed the ongoing fight between trucking interests and safety advocates over the role that fatigue plays in crashes.

Brown noted that Public Citizen puts the range of fatigue-related crashes between 13% and maybe more than 30%, and ATA puts it at about 2.2%.

“We hardly think it proper to second-guess the agency’s decision to employ a 7%-to-18% range,” she wrote.

It remains to be seen, however, if Brown’s conclusion about the impact of today’s decision will hold.

“With one small exception, our decision today brings to an end the permanent warfare surrounding the HOS rules,” she wrote.

The rule has been in constant litigation for the past decade and today’s decision is unlikely to resolve hostilities.

For instance, it seems clear from Public Citizen’s commentary that the group will continue to resist the 11-hour driving limit.

For the full story, including industry reaction, visit Today’s Trucking’s editorial partner, Heavy-Duty Trucking here.