In 2013, Mats Järlström's wife got a $260 ticket in the mail for running a red light.
It wasn't exactly the crime of the century. A camera caught her Volkswagen passing through a Beaverton, Ore., intersection 0.12 second after the light turned from yellow to red.
Other people might curse, pay the fine and forget about it.
But Järlström, who earned a degree in electronic engineering in Sweden, got curious: How are yellow lights timed? He decided to investigate.
Little did he know that his quest would land him with an even bigger fine and morph into a battle over free speech rights.
Järlström, a 57-year-old green card holder, moved to the U.S. in 1992 and says he now works as a consultant who helps companies repair electrical instruments. He doesn't have an engineering license, but he proudly calls himself "a Swedish engineer" who wants to improve his community.
"Instead of being interested in how to do something in a new way or understand that they're not doing something correctly, they wanted to shut me up," Järlström said in an interview. "Traffic safety in Sweden is 250% better than the USA. It's not only that we are driving Volvos. It's that we have good engineers who are well educated and understand things.
"I just wanted to contribute," he said.
In Beaverton, the yellow lights were supposed to last exactly 3.5 seconds.
But using a stopwatch and two high-definition video cameras, Järlström ran his own tests on the intersection where his wife was ticketed. He said his findings showed that the intersection's yellow lights ran on average 0.14 seconds, or 4%, shorter than advertised. He complained to the city.
"You might think this error is small but put into perspective a watch would add one full hour every day! (24 hours * 4% = 0.96 hours or 57.6 minutes)," Järlström wrote in a memo to the City Council. "Not acceptable accuracy with today's technology — the ancient Greeks had better timing devices!"
City officials weren't convinced that anything was wrong — and neither was a judge, who looked at Järlström's research before upholding his wife's ticket.
Järlström also sued the city in federal court over its lights, but a judge ruled that the lawsuit lacked federal standing and threw it out.
But Järlström started looking at the bigger picture: Was 3.5 seconds even the appropriate length for a yellow light?
Drivers have long faced the same problem as the light turns yellow: "Whether to stop too quickly (and perhaps come to rest partly within the intersection) or to chance going through the intersection, possibly during the red light phase," wrote the authors of a 1959 study who called the problem the "dilemma zone."
Taking into account traffic speed, driver reaction and other variables, the paper presented calculations to measure the dilemma zone that would eventually inspire formulas for yellow lights adopted by the Institute of Transportation Engineers, an international association that is influential in the arcane world of traffic technology.
Järlström concluded that the formula did not sufficiently account for drivers slowing to make turns, making yellow lights too short for some drivers.
By then, his mission had morphed from fighting her ticket to changing public policy.
In messages sent to a national engineering association and to the CBS News show "60 Minutes" in 2014, Järlström boasted that his formula "will have worldwide impact."
"I have actually invented and publicly released a new extended solution to the original problem with the amber signal light in traffic flow," he wrote a year later in an email to Patrick Garrett, the Washington County sheriff.
But some of the biggest interest came from the Oregon State Board of Examiners for Engineering and Land Surveying, which regulates engineers in Oregon. After the board received an email from Järlström in 2015 presenting his idea, it launched an investigation — into Järlström.
On Nov. 1, 2016, the board sent him an civil notice finding that he was practicing engineering without a license and fined him $500.
"By asserting to a public body in correspondence that he is an ('excellent') engineer, and asserting to the public media in correspondence that he is a ('Swedish') engineer, Jarlstrom held himself out as, and implied that he is, an engineer," the board wrote in its citation.
State licensing laws exist to prevent the public from being harmed by untrained people purporting to be experts. But Jarlstrom did not think he needed to be a licensed engineer to critique public policy.
He sued the state licensing board with the backing of the Institute of Justice, a libertarian organization, for allegedly violating his 1st Amendment free speech rights.
"Järlström wants to write and speak publicly about a matter of local, state and nationwide concern: the safety and fairness of traffic lights and traffic-light cameras," the lawsuit said.
It also argued that state law created "a government-run monopoly on engineering concepts generally."
The board eventually backed down and agreed it had violated Järlström's free speech rights by applying the state's engineering restrictions to Järlström "in a noncommercial and nonprofessional setting."
However, the case remains unresolved, as Järlström wants a broad ruling from a judge that will bar the state from challenging his standing as an engineer in the future, while the state still wants to regulate who can call themselves an engineer, citing public safety.
"Effectively they are trying to make this case go away while preserving as much as their rights as possible," said Järlström's attorney, Sam Gedge.
The state board did not respond to messages seeking comment.
Nearly lost in the debate is whether Järlström's ideas have scientific merit. The Institute of Transportation Engineers took them seriously enough to let him make a presentation of his work at its conference in Anaheim in August 2016.
But Järlström said he is afraid to release more of his research on stoplights to the public without a ruling allowing him to call himself an engineer.
"In Sweden, you don't have those issues, and I feel completely violated that I can't say who I am," Järlström said. "It's a human right, and I think it's an international right. Geneva Convention in wartime. You have a right to say who you are."
Matt Pearce is a national reporter for The Times. Follow him on Twitter at @mattdpearce.