When California Sen. Scott Wiener introduced a bill earlier this year to curb speeding, he expected some resistance.

But the intensity of the response caught the Democratic lawmaker from San Francisco by surprise.

“That really hit a nerve,” Weiner said in an interview. “The day I announced the original bill, one of my best friends in the world texted me to say what a terrible idea it was. And 10 minutes later, his boyfriend texted me to say, ‘Thanks for making my boyfriend get fired.’”

Your car probably tells you when you’re low on gas. It can warn you when you’re drifting out of your lane. Now, California lawmakers want to go a step further by requiring the technology in your car to warn you when you’re speeding.

Safety advocates say speed enforcement technology can reduce road deaths, but critics say California is moving too quickly.

“They’re trying to impose their will on the rest of the country,” said Jay Beeber of the National Motorists Association, a drivers’ rights group.

To understand why Wiener’s bill has been so divisive, it’s worth understanding how speed-assist technology works. There’s an “active” version that can physically stop drivers from exceeding the speed limit. But there’s also a “passive” version of speed-assist that only warns drivers when they’re going too fast.

After initial opposition, Wiener changed his bill from active to passive speed assistance systems. And while some safety advocates may be disappointed, Wiener defends the decision.

“We listened and we heard,” Wiener said. “When we looked at the research, we saw that the passive speed limiter is also very effective. That’s why I felt comfortable making this change.”

Political calculations also came into play.

“The law would not have been passed with an active speed limiter,” Wiener admitted. “And it was passed with a passive speed limiter.”

A bill approved by the California Legislature over the weekend would require all new cars sold in the state to warn drivers if they are going more than 10 miles per hour over the speed limit. California would be the first state in the country to make the speed-assist technology mandatory, starting with the 2030 model year.

The bill has its ardent supporters, including the National Transportation Safety Board.

“Wide implementation of intelligent speed enforcement assistance would reduce the incidence of speeding and speed-related crashes … saving lives and preventing injuries,” the NTSB said. wrote in support of a bill in California“and we commend you for implementing this policy.”

The NTSB can make recommendations, but it cannot force automakers to add speed control assist systems.

Critics of the California bill say it is too drastic and comes too soon.

“The technology is not perfect,” Beeber said in an interview. “You’re going to have a lot of false positives.”

Speed-assist technology is easily confused, Beeber says, especially between highways and nearby streets with widely different speed limits. He believes that will be annoying and potentially distracting for drivers.

“Unfortunately, our cars right now are kind of in the business of distracting us,” Beeber said. “I think that increases distraction while driving.”

The automotive industry is also unhappy with the roadside assistance law.

Speed ​​assist systems “rely on clear and visible speed limit signs posted at regular intervals to function properly,” industry trade group Alliance for Automotive Innovation wrote in a comment opposing the bill.

“This type of infrastructure is available in Europe,” where passive speed assistance is already mandatory. “But in the U.S., it is very scarce. As a result, many/most intelligent speed assistance systems are flawed and unreliable in the U.S.,” the group wrote.

“This is another example of California overreaching,” Karen Bailey-Chapman of the Specialty Equipment Market Association, an industry trade group, said in an interview.

California is a huge market for automakers, and Bailey-Chapman says the state is trying to exert pressure to decide policy across the country.

“We believe that the authority to make regulations remains with the federal government,” she said.

But the bill’s author, Scott Wiener, says California can’t wait for federal regulators.

“I would like to see the federal government require this technology on a national level,” he said. “But there is no indication — no real indication — that the federal government is going to do that.”

Wiener compares the situation to the early 1960s, when Wisconsin introduced a seat belt requirement more than six years before the federal government did so.

“How many lives were saved when Wisconsin got ahead of the federal government in 1962 and mandated seat belts, which started a domino effect nationwide?” he asked.

California’s roadside assistance bill now heads to Gov. Gavin Newsom’s desk, where he has until the end of the month to decide whether to sign it.

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