The cloud of thick, jet-black smoke billowed out over the tailpipe every time the large pickup truck accelerated away from a red light as a friend and I followed it through town.

“That’s awful,” she said.

“That’s intentional,” I replied, pointing out the “Colorado Coal Rollers” sticker in the rear window.

Fewer things say “I’m a jerk, and I don’t care about anybody else” than those guys — and they’re almost always guys — who modify their diesel pickups with intentionally dirty exhaust systems.

“Rolling coal,” which typically features over-fueling a diesel engine and tampering with exhaust-control systems to produce excessive smoke, in recent years has become popular among a certain set of pickup drivers who take delight in enveloping pedestrians, bicyclists and Prius drivers with thick billows of black smoke while offering a Bronx cheer to the rest of the world.

As a bit of a social experiment, I snapped a photo of the offending truck as it was chugging away like a coal-fired locomotive and posted it on a local community page for Facebook, intending to provoke reactions and, admittedly, hoping to do some “smoke shaming.”

“Obviously compensating,” one commenter replied.

“Shoot him!” wrote another.

“Immaturity personified,” added a third.

The responses were overwhelmingly negative, although one local conservative activist offered a bit of a defense by derisively suggesting that she was looking forward to “beachfront property at 8,500 feet” due to climate change.

Then, to my surprise, one guy wrote: “Hey, that’s my truck.”

For a brief moment, I felt a pang of regret — there was an actual person on the front end of that smokestack, and suddenly the anonymity of the internet was broken down by the presence of humanity — but, as the online conversation unfolded, my initial disdain quickly was reinforced.

“Can’t wait for the summer when the bikes come out and they think they own the road,” the truck owner wrote. “I like to show how much bigger my truck is and how I’ll win.”

He denied that the truck was modified to pollute intentionally, suggesting instead that he was seeking more power. “It only smokes when I get in it or at a stop with no boost build up.”

I expressed skepticism, pointing out that the “rolling coal” sticker hardly creates plausible deniability, and he responded that he was “doing nothing against any law.”

While being a jerk isn’t against the law, blowing excessive smoke technically is illegal in Colorado — although punishable only by a $25 fine for a first offense.

But just this past week, the Republican-controlled state Senate Transportation Committee killed on a party-line vote a bill that could have meant up to 90 days in jail and a $300 fine, plus three points on the driver’s license of coal rollers who blow smoke intentionally to harass or obscure the view of another driver, pedestrian or bicyclist.

In an age when vehicle manufacturers rightfully brag about developing “clean diesel,” even advocates are red-faced by the black smoke.

“The diesel industry is extremely disappointed that a small segment of diesel pickup truck owners have chosen to … deliberately produce black smoke,” wrote Allen Schaeffer, executive director of the Diesel Technology Forum, a non-profit educational group. “This practice of ‘rolling coal,’ which has targeted drivers of hybrid vehicles, pedestrians, bicyclists, law enforcement and others, is dangerous, harmful to the environment and illegal. We urge state and local air quality and law enforcement officials to fully enforce all clean air and vehicle emission laws available to stop this unlawful practice.”

Have no doubt, coal rollers are making a statement: They disdain environmental concerns, dismiss political correctness and disrespect anyone who objects. They are intentionally conspicuous, loud and brash — in a word, bullies who gleefully enjoy belittling and demeaning others.

Perhaps the best way to fight back is to report coal rollers to the Colorado Department of Public Health and Environment’s smoking-vehicle hotline at 303-692-3211, and to push elected officials for stronger local and state laws against the practice.

Of course, coal rollers and their defenders will accuse critics of being overly sensitive, irrationally concerned and humorless. They’re simply blowing smoke.

Steve Lipsher (slipsher@ comcast.net) of Silverthorne writes a monthly column.

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