Early on March 6, Juanisha C. Brooks was driving home on the Capital Beltway when she saw the flashing lights of an emergency vehicle behind her. At first she thought it was an ambulance, and she steered to the shoulder of an exit ramp to let it pass.

Brooks soon realized she was being pulled over, drove from the ramp to the first side street and stopped.

There, Brooks repeatedly asked Virginia State Police Trooper Robert G. Hindenlang why he had pulled her over, and Hindenlang repeatedly refused to say, dashboard-camera video from the trooper’s car shows. He did not tell her he had noticed her taillights were out as she drove. Instead, he told Brooks that if she would step outside, he would show her why she had been stopped. Brooks told the trooper she didn’t want to get out.

Hindenlang then unlocked Brooks’s door and dragged her out of the car, while Brooks loudly pleaded with him to stop, the video shows. The trooper spun her against the car and handcuffed her. When Brooks refused to take a sobriety test, after telling the trooper she had had one drink, Hindenlang told her, “You’re under arrest for driving under the influence.”

“Why were your eyes so watery when I pulled up?” Hindenlang asked her.

“Why were my eyes watering?” Brooks, who is Black, answered the trooper. “Because people are being shot by the police. I’m freaking nervous.”

At the Fairfax County jail, Brooks and her attorney said, she twice took a breathalyzer test. The results: a 0.0 blood alcohol level. So Hindenlang charged her with resisting arrest, eluding police, failing to have headlights on and reckless driving.

Brooks said she had forgotten to turn her headlights on that night and hadn’t noticed on the brightly lit Beltway. The Virginia General Assembly banned pulling people over for dark taillights, effective March 1, because it led to the type of pretextual traffic stops that can cause unnecessary conflict and consequences for otherwise law-abiding citizens.

After Brooks’s attorney, Patrick M. Blanch, provided the video to prosecutors, Fairfax Commonwealth’s Attorney Steve Descano dismissed all charges and called for state police to conduct an internal investigation. In a letter to police, he said that “the stop was without proper legal basis,” given the recent change in the law, and that the “dashcam footage does not provide a factual basis to support the warrants.”

Corinne Geller, the spokeswoman for the Virginia State Police, said the stop and arrest were proper. She said Hindenlang observed Brooks driving “without any headlights or taillights, tailgating other vehicles and making unsafe lane changes, which are indicators of an impaired driver and provided reasonable suspicion for the trooper to initiate a traffic stop.” Geller said Brooks was taken into custody “due to her persistent refusal to comply with the trooper’s requests” and because of the trooper’s suspicion that Brooks might have been driving under the influence.

Traffic stops are one of the most common places for citizens to interact with police. But because they have the potential to quickly turn confrontational, such as during the stop that led to the recent police killing of Daunte Wright in Minnesota, many jurisdictions are considering limits on what police may treat as a cause for stops or searches. Virginia lawmakers recently prohibited police from making stops for dark taillights, the smell of marijuana or something dangling from a rearview mirror. The D.C. Police Reform Commission has found that even in areas of the District where White residents are the majority, Black people make up a majority of police stops. Last week, the Minnesota legislature debated a bill limiting pretextual stops by police over minor infractions.

“Officers who conduct stops about traffic safety,” said Lauren Bonds, legal director of the National Police Accountability Project, “are trained to convert them into investigative stops, looking for drugs, looking for a reason that would justify more of a search. … I think it really undermines public confidence in the police. If I was Ms. Brooks, I don’t think I would ever want to stop for the police again.”

Brooks, a Defense Department employee with a top-secret clearance, said the encounter left her fearing for her life and later her job.

“I’m nervous because I’ve seen so many of these interactions,” Brooks said in an interview. “I was having a panic attack. … I felt to get out, I would be putting myself in danger.”

Brooks has worked for the Defense Department for eight years, currently as a senior video producer. With top secret clearance, “My whole livelihood was on the line,” Brooks said. “You can’t have any charges when you have a clearance.” The Defense Department questioned her about the arrest, she said.

Hindenlang, 49, has been a state trooper for 24 years, Geller said. He does not have a voice mail or answering machine on the phone number listed for him, and he did not respond to an email seeking comment. The state police said they are conducting an internal investigation of the incident.

Brooks’s ordeal didn’t end with being charged, though. Hindenlang had ordered her car towed, and left her wallet and phone inside the car. After Brooks was released on a signature bond, she said she asked Hindenlang where her car was, and he gave her a sticky note with the name of the tow lot in Lorton, but nothing else. Brooks said Hindenlang told her that her mother was waiting in the lobby and could help her. Brooks’s mother is deceased.

“Oh,” Hindenlang said, then shut the door on her and walked out, Brooks said.

A bondsman tried to help her contact friends, and eventually the magistrate in the jail sympathized with Brooks and drove her to the Vienna Metro station and gave her $20, Brooks said. The station wasn’t yet open, so she stood outside in the frigid darkness for an hour. It took a train ride, two bus trips and a cab ride for Brooks to reach the tow lot, where she said she was charged $240 to extricate her car. She arrived home around noon, almost 10 hours after Hindenlang stopped her.

“Would he have done that to a White woman? No,” Brooks said. “He didn’t see me as a human being. … This has to stop. It’s racism at its core, and it should be seen as such.”

Geller denied any racial component to the stop. “At no time during the traffic stop,” Geller said, “did any Virginia State Police personnel make a direct or indirect reference to Ms. Brooks’s race, ethnicity, nationality or gender.” She said that Brooks’ phone and wallet were placed in her car to decrease the chance of their being lost while she was being taken to jail and that “a trooper is only required to transport an individual in custody, not personal possessions.” Once Ms. Brooks was released from the jail, she was no longer in police custody, Geller said. “State police does not provide individuals rides home from jail,” she said.

Jordan Blair Woods, a professor at the University of Arkansas law school and author of a recent law review article titled “Traffic Without the Police,” watched the video of Brooks’s traffic stop. “It’s disturbing,” Woods said. “If a driver doesn’t immediately pull over, even if they’re in the middle of a dark highway and confused, the first hunch an officer has is the driver has something to hide or is involved in criminality. That’s an assumption that, unfortunately, is ingrained in the law.”

“This traffic stop,” said Claire Gastañaga, executive director of the American Civil Liberties Union of Virginia, “is a perfect illustration of why the General Assembly made it illegal for police to do a traffic stop for no taillights as a primary offense as of March 1, five days before this stop took place. The trooper unnecessarily escalated this situation in a circumstance in which a contributing factor clearly was the trooper’s own failure to show any empathy for why a Black woman might be afraid to stop for police late at night.”

Brooks said she had bruising on both arms and pain for weeks, but also, “I went through emotional trauma. I haven’t slept a full night since. Three hours here, four hours there. Every single day I think about it.”

Brooks is a native of Portsmouth, Va., a graduate of Virginia Tech and serves on the board of directors of the university’s alumni association. Brooks’s sister was visiting from Portsmouth, and the pair met for about two hours late on March 5 into March 6. She said she had one cocktail around midnight. Hindenlang wrote in his report that he detected “a fruity smell coming from her person,” suspecting it might be alcohol. Brooks said it was her perfume.

Brooks was heading to her home in the Kingstowne area of Fairfax County, driving west on the inner loop of the Beltway, shortly after 2 a.m. Hindenlang and a trainee trooper were parked on the on-ramp from Telegraph Road when they spotted the car with no taillights go past, the video shows. The audio was not on as Hindenlang pulled out, and within 40 seconds he reached Brooks’s Honda Accord and followed it.

Georgetown University law professor Paul Butler recently told an interviewer for NPR that he brings a police officer into his classes who invites students to ride with him to witness his power. “He tells the students, ‘Pick any car you want on the street and I’ll stop it,’ ” Butler said. “He’s a good cop. He waits until he finds a legal reason, but he says that he can follow any car for four or five minutes and he’ll find a reason. There’s so many traffic infractions that any time you drive, you commit one. And that gives police an extraordinary amount of power, and we know that they selectively use this power against Black and Brown people.”

Though Geller said that Hindenlang “observed the Honda traveling on I-495 without any headlights or taillights,” Hindenlang’s written report does not mention Brooks’s car failing to have headlights on, nor does he mention that in the video. The Accord did have front running lights on, the dash camera shows. Hindenlang wrote that Brooks’s car was, on two occasions, “following the other vehicle at two car lengths” and that in one instance where Brooks’s lane ended, she merged “without signaling.”

After two minutes, Hindenlang decided to pull Brooks over. Brooks said initially she thought the flashing lights were an ambulance and slowed down on the Van Dorn Street exit ramp to let it pass. When she realized it was a police car, not an ambulance, Brooks said she drove to a nearby street with which she was familiar and stopped.

Some police departments, including in Fairfax County, require their officers to identify themselves and state the reason for a stop. The Virginia State Police does not require this. The video shows that Hindenlang asked Brooks whether she had a license and registration, which she said she did, and to get out of the car, but he ignored her questions about why she was stopped. He said that if she got out, he would show her the reason, but Geller said the real reason for the request was to stop Brooks from driving away.

Police have the legal authority to order a driver out of a car to protect themselves. The U.S. Supreme Court said in 1977 that “what is, at most, a mere inconvenience cannot prevail when balanced against legitimate concerns for the officer’s safety.”

Brooks said she thinks that if she were White, the trooper would have asked her about her taillights and suggest she get them fixed, as she said happened with a White colleague recently. She tried to begin recording the encounter on her phone, but instead the trooper “grabs me by left hand and yanks me out of the car,” causing her phone to fall to the ground, Brooks said.

“I’ve seen how these situations play out,” Brooks said. “I was in fear for my life, that I would be shot.” The elapsed time from when Hindenlang first signaled Brooks to pull over to when she was handcuffed was less than five minutes. Hindenlang then questioned Brooks about whether she had been drinking.

“The trooper afforded her the opportunity to complete field sobriety tests to confirm her sobriety,” Geller said, “but she refused.” Brooks said she declined the tests because she didn’t believe they would be fairly administered.

“My global impression of the stop,” said Bonds, of the National Police Accountability Project, is “there were just an escalating number of pretextual reasons that the officer was upset that he wasn’t getting enough deference from Ms. Brooks.”

Descano, the Fairfax prosecutor, said in a statement: “It’s sickening and unacceptable that any member of our community fears for their safety during a routine traffic stop. That’s why I will not rest until we bring about the day when this is no longer the case.”