A bill that would have made it a felony to not immediately comply with a traffic stop when you're pulled over by an unmarked police car — even one that's not acting in an emergency capacity — has failed in the Arizona Senate.

House Bill 2384, introduced by Representative Todd Clodfelter, a Tucson Republican, targeted anyone who "willfully flees or attempts to elude a pursuing law enforcement vehicle."

The bill was backed by local police unions, including the Arizona Police Association, Phoenix Law Enforcement Association, Combined Law Enforcement Associations Of Arizona, Associated Highway Patrolmen of Arizona, and the Fraternal Order of Police's Arizona State Lodge.

In theory, the proposed law was intended to crack down on high-speed chases. The problem, critics say, is that the language didn't leave room for drivers who aren't sure whether the unmarked car pulling them over really belongs to a cop.

"We were concerned that it could create situations where women would be pulled over, and not feel that they were in a safe place," said David Euchner, a public defender in Tucson who previously served as president of Arizona Attorneys for Criminal Justice.

In recent years, there have been several examples of people impersonating cops, and then either robbing or sexually assaulting drivers:

• In March 2015, a man with red-and-blue flashing lights on his dashboard tricked a woman into pulling over, "then asked her for sexual favors to avoid going to jail."

• In May 2017, a man impersonating an officer stole the personal property of a driver who'd he'd pulled over in Phoenix on the pretense of conducting a traffic stop.

• Last November, a woman in Eloy reported that a police officer had groped her during a traffic stop. When the Eloy Police Department investigated, they discovered that the man wasn't actually a cop, but an impersonator.

• In February, a 66-year-old woman in Phoenix was pulled over by a Ford truck with red-and-blue flashing lights. When her granddaughter noticed that the driver was wearing a tank top, she became suspicious and pulled out her phone to take a picture. The man immediately fled.

In order to charge someone for unlawful flight from an unmarked car, prosecutors would only have had to prove that the driver knew that the unmarked car was an official law enforcement vehicle. The police car would not necessarily need to have been operating in an emergency capacity at the time.

"What is going to be the evidence that shows that the person knew?" Euchner asked. "It was too overbroad."

After clearing the Arizona House of Representatives, the bill failed in the Senate after receiving a tied 15-15 vote. Two Republican women — Sylvia Allen and Kate Brophy McGee — joined Democrats in voting against it.

"When you are traveling in Arizona, sometimes you can be — I don’t want to say targeted, but you can be vulnerable," said Senator Jamescita Peshlakai, a Democrat from the Navajo Nation. "As a person of color, I know this to be true."

She added, "If I were to be pulled over at night by a police officer, I probably wouldn’t even pull over at all."