In this Sept. 11, 2015, file photo, Benjamin Scott Brewer, center, appears for his arraignment in Chattanooga, Tenn. Federal investigators say Brewer failed to slow down in a construction zone, was probably fatigued and had taken methamphetamine to stay awake. Brewer’s tractor-trailer crashed into multiple vehicles on Interstate 75, killing six and injuring six others on June 25, 2015. (Dan Henry/Chattanooga Times Free Press via AP, File)

Last year, the National Transportation Safety Board was called in to investigate a deadly crash involving a trucker in Tennessee.

What the NTSB didn’t do after wrapping up its investigation is as interesting as what it did. It’s something that might apply to other situations and institutions where laying down new rules might not be the answer to ingrained problems caused by people who don’t follow them.

On June 25, 2015, Benjamin S. Brewer was at the wheel of a Peterbilt tractor-trailer on Interstate 75 near Chattanooga after approximately 12 hours on the road, according to the NTSB and media reports. He was tired, having ignored rules requiring him to take appropriate breaks since the start of his run about 5 a.m.  He was also illegally cranked up on methamphetamine, the agency found.

As traffic slowed to a crawl at a work zone, Brewer’s truck barreled on at a speed of at least 78 mph, triggering a chain reaction crash. Six people were killed; four were injured.

The NTSB investigation found that Brewer was impaired by fatigue and drugs and broke several rules designed to prevent such a crash. As it turns out, Brewer, 39, had also been had been fired from a previous trucking job two years earlier because of illegal drug use, the Associated Press reported.

Since the NTSB’s mission is not to fix blame but to improve transportation safety, agency officials searched for recommendations that might prevent such crashes in the future.

But what good is writing new rules when the existing ones are adequate and people simply choose to ignore them? Robert Molloy, director of the NTSB Office of Highway Safety, spelled out that dilemma in a recent post on the agency’s website. His response?  Do a better job hiring to keep risky drivers off the road in the first place.

In the Tennessee crash, for example, the NTSB found that although the trucking company had reviewed Brewer’s driving record before hiring him, inadequacies in the records from Kentucky and Idaho prevented the company from knowing about previous crashes and citations. The NTSB says Brewer’s trucking company also could have tested Brewer’s hair for previous drug use before it hired him.

So instead of layering on new rules or regulations about drugs or fatigue that already apply to truckers, the agency urged the Federal Motor Carrier Safety Administration (FMCSA) to strengthen the trucking industry’s screening of prospective drivers.

“One way to make progress toward these goals is to ensure that truck drivers with a demonstrable pattern of unsafe behavior are filtered out of the transportation system before their behavior results in tragedy,” Molloy wrote.

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