If Galileo or da Vinci, the famed Italian polymaths, lived in modern day Oregon, they might well be the targets of a lengthy and expensive inquisition by the Oregon State Board of Examiners for Engineering and Land Surveying for the unlicensed practice of engineering for engaging in mathematical criticism. That is because neither became state-licensed professional engineers before they publicly questioned the prevailing scientific establishment of their day.

Although Oregon resident Mats Järlström’s mathematical theories are more earthly than Galileo’s or da Vinci’s, he faced a similar inquisition by the Oregon engineering board after he publicly criticized the standard formula used to time yellow traffic lights.

But now Mats, working in partnership with the Institute for Justice, is fighting back against the state’s unconstitutional ban on mathematical debate. Today he filed a lawsuit against the board in federal court challenging the constitutionality of the state’s requirement that citizens must obtain an engineering license in order to publicly debate anything involving “engineering.”

“Criticizing the government’s engineering isn’t a crime; it’s a constitutional right,” said Sam Gedge, an attorney at the Institute for Justice, which represents Mats in the lawsuit. “Under the First Amendment, you don’t need to be a licensed lawyer to write an article critical of a Supreme Court decision, you don’t need to be a licensed landscape architect to create a gardening blog, and you don’t need to be a licensed engineer to talk about traffic lights. Whether or not you use math, criticizing the government is a core constitutional right that cannot be hampered by onerous licensing requirements.”

It all started in 2013 when Mats’s wife received a red light camera ticket, which sparked Mats’s interest in how exactly yellow lights are timed. He began writing and speaking publicly about how red light cameras misuse the standard mathematical formula for timing traffic lights, leading to unsafe driving conditions and unfair citations when drivers slow down to turn. People wanted to hear Mats’s ideas—local news covered his story and he presented his research at a national conference of the Institute of Transportation Engineers.

But Oregon’s engineer-licensing board had heard enough.

After a two-year investigation, the board fined Mats $500 for the unlicensed practice of engineering. If Mats continued to “critique” traffic lights, he could face thousands of dollars in fines and up to one year in jail for the unlicensed practice of engineering.

The Oregon State Board of Examiners for Engineering and Land Surveying also said that Mats cannot even call himself an “engineer,” even though he has a degree in electrical engineering and decades of experience in technical fields. Like most engineers in Oregon, Mats is not a state-licensed “professional engineer.” (A professional engineer is the specialist who would be responsible for designing a bridge or the electrical system for a school.) Yet the board thinks that only licensed professional engineers should be able to call themselves “engineers.”

“People should be free to debate any topic, including technical topics like math and traffic lights,” said IJ Client Mats Järlström. “But I was fined simply for speaking out and was told that I can’t truthfully call myself an engineer. The board has not only silenced me, it has silenced many other people who want to talk about technical issues.”

In recent years, the board has launched investigations against similar speech in voter guides, a town hall meeting, a political ad and even in the “Oregon Women 2015” edition of Portland Monthly. One retiree was fined hundreds of dollars for complaining about his flooded basement. When he wrote to the Board seeking help, the Board fined him for truthfully calling himself a “professional engineer” in his letter, because he had been licensed in another state.

“You don’t need a permission slip to criticize the government,” said IJ Attorney Wesley Hottot, who also represents Mats. “This board, and licensing boards across the country, think the First Amendment doesn’t apply to them. They couldn’t be more wrong.”