Nobody liked working “duty day” but, as the name implied, it wasn’t a choice. About once a month, each of us in the public defender’s office set aside our cases and took a turn serving as a lawyer for the general public. Whoever walked in or called in became your responsibility. One of my first murder cases began when a mother called to say that her son was at police headquarters speaking to homicide detectives. She thought he might be a suspect and wanted to know if it was a good idea for him to be talking to the police. (Answer: no, it wasn’t.)

But duty day mostly involved issues that were less attention-grabbing. I once counselled a grandmother who feared she would lose her public housing if she allowed her grandson to move in with her on his release from prison; housing authorities were notoriously hostile to people with criminal convictions.

By far the most common duty-day requests were from people trying to get their arrest warrants sealed. These cases were as difficult as they were frequent. In Washington DC, as in most of the US, there were few legal grounds to erase an arrest from your record, even if the case was quickly dismissed and never led to a criminal conviction. But despite the long odds of success, there was at least a way for individual citizens to make the request, by filing a relatively simple legal motion. It was our job to tell people about the law, give them a copy of the paperwork, and show them where to fill in the blanks. These consultations normally took less than 20 minutes.

But Sandra Dozier clearly had no intention of leaving so quickly. In her early 30s, with a short-cropped afro and a determined manner, Dozier was telling me about the traffic stop that had led to her arrest. After hearing the words “arrest” and “clear my record”, I had assumed she needed the simple motion to seal. But she kept talking, barely glancing at the forms I pushed in her direction. Since I could see she wasn’t going to leave until I had heard the entire story, I took out my yellow legal pad and started taking notes.

In February 2000, Dozier had been driving home from her mother’s house, along with her 19-year-old cousin and two-year-old daughter. She was on Alabama Avenue in south-east DC when a police car pulled up behind her with its lights flashing. After she pulled over, an officer came to her window and asked her for her licence and registration. She gave them to him, but not before asking, “Why are y’all messing with me? I’m coming home from work.” I didn’t ask, but I thought I knew why she had mentioned her job. The area where Dozier lived and had been stopped suffered from chronic unemployment. People who worked were quick to use that fact as a form of character evidence when confronted by police or other authorities.

Without answering Dozier’s question, the officer took her documents back to his police car. A few minutes later, he returned and told her he needed to check if the tint levels on her windows were “too high”. It was a common tactic: traffic regulations in DC and elsewhere often limit how dark a car’s windows can be. Stops for exceeding the tint limits were a police favourite. Dozier told the officer he must be mistaken; she had had the tinting done at a reputable place where they knew what was permitted.

Despite her protestations, the officer said he needed to check anyway. “We’ve been having a lot of problems with shootings and guns and weapons out here,” he told her. “Do you have anything like that with you? In the car?” Dozier remembered thinking that the officer must be crazy – what would she be doing with anything like that? One of her brothers had been shot a few years before, and another was locked up on a gun charge, and she was determined to stay far, far away from all that. She told him: “You have the wrong person if you are looking for guns.”

She said the officer nodded, and seemed to understand where she was coming from. Then he said: “Since you don’t have anything, you don’t mind if we check real quick?”

I had been expecting this. I didn’t know the precise words the police would have used – those varied – but I knew that at some point during the encounter with Dozier, they would have tried to search her car. That was, after all, the entire point of the stop.

To understand what was happening to Dozier, it is crucial to distinguish between the various types of traffic stops conducted by US police. Not all stops are created equal. Sometimes the police pull people over for traffic-safety reasons – for speeding or running a red light, for example. More nefariously, recent reports by the Department of Justice and others have shown that police departments in Ferguson, Missouri, and elsewhere have used traffic enforcement to generate fines to fund local government.

But Dozier had fallen prey to another type of traffic stop, one whose motive is neither traffic safety nor revenue enhancement. This kind of stop – an investigatory or pretext stop – uses the traffic laws to uncover more serious crime. Such stops (and subsequent searches) exploded in popularity in the 1990s as part of police efforts to target drugs and guns.

Like most of my clients, Dozier didn’t think she could refuse. As she explained: “I figured they would search if they wanted to, regardless, so I thought, if I say yes, maybe they won’t even bother, since they will see I have nothing to hide.” As she had promised, there were no guns or weapons to be found. But a second officer on the scene did find two small baggies of marijuana, worth about $20, in the glove compartment.

When the officer emerged holding them, Dozier lost it. “I started crying, telling them I couldn’t be locked up for this, that I had just started a new job, that I had to be at work in the morning, that I couldn’t miss work or I’d be fired.”

The two officers conferred, and after a few minutes the first one came back. He seemed to have good news. Since Dozier had no record or outstanding warrants, he could release her from the police station with a citation to appear in court. This was much better than the alternative, in which she would be held in jail overnight and wouldn’t see a judge till sometime the next day, missing work as a result. A few weeks later, she went to court and, after waiting all day, was told the marijuana possession charges had been “no papered”, meaning the prosecutor’s office had decided not to bring charges. She had no pending charges and no criminal conviction. She was a free citizen in the eyes of the law.

So what was she doing in my office? Dozier had been a new employee at FedEx, and at the end of her probationary period she was asked to bring proof of a clean record. This was a routine request, but in Dozier’s case the paperwork came back showing her recent arrest for marijuana possession. And FedEx promptly fired her.

Facebook Twitter Pinterest Police performing a traffic stop and vehicle search in New Town, North Dakota. Photograph: The Washington Post/Getty Images

She opened a folder and put some papers on my hopelessly cluttered desk. On top was a printout I had seen many times. It was from the Washington DC superior court clerk’s office, and it contained Dozier’s criminal record. An eight-hour duty-day shift typically included three or four inquiries from frustrated citizens who had requested proof of a clean record to give their employers, only to find that the police, or the superior court, still had evidence of a past arrest on file. The system sometimes seemed like a lottery: I had seen cases in which it missed multiple arrests for a single individual, and others in which it had captured every detail, even a minor citation such as this one.

As I looked down at the printout, I couldn’t help but notice how unusually “clean” Dozier’s record was. It was rare for me to encounter somebody whose only criminal involvement was a single no-papered arrest for marijuana possession.

“So, can you help me?” she asked.

It looked bleak. As a casual employee on probationary status, she had almost no job protection. The law permitted employers to consider any criminal record – including arrests – in making hiring decisions. I told her this, and her body seemed to shrink in her chair. Nobody came to our office if they had other options, and now her lawyer of last resort was letting her down too. Desperate to try something, I told her: “Well, I can call FedEx and see if I can talk them into giving you another chance.”

Dozier liked the idea. She was organised and prepared, and she fished her supervisor’s phone number out of the sheaf of papers she had with her. I got him on the phone.

“I’m calling on behalf of Sandra Dozier,” I said, and launched into my pitch. I focused on the prosecutor’s decision not to bring charges, and explained that only the most frivolous cases got no-papered. I pointed out that an arrest wasn’t a conviction, that the case had been dismissed and that she had no pending charges. She would never need to miss work for a court hearing or probation appointment. Legally, I told him, she was a person with a clean record. She was a free citizen who deserved the chance to keep her job.

The supervisor was sympathetic. He said that he liked Dozier, had been rooting for her and was very disappointed when the record check came back with an arrest. It was one of the final stages of the process before an employee moved off probationary status. He even agreed that marijuana possession was a small-time charge.

I was on the verge of giving Dozier a thumbs-up sign when he said: “But here is the thing. It isn’t my decision. We have a firm policy that if you get arrested while you are on probation with us, we can’t hire you.”

I started to reply, but he shut me down.

“Look, that’s all there is to it,” he said. “It’s company policy. It’s done. I’ve got to go.” I murmured my thanks to him for taking my call, and we both hung up.

I didn’t have to relay the details to Dozier. She could read the bad news on my face, in my tone of voice, and in the abrupt way the call had ended. I tried to think of something positive to say, but I had nothing to offer. The call had been my last shot, and it had failed.

Dozier was gathering up her things and heading for the door when I remembered that my office had recently got copies of fliers for an upcoming job fair hosted by the DC government and various employers. Maybe this would help?

As soon as I handed her the flier, I could see it was a mistake. She glanced at it for all of two seconds, then looked up at me with a mixture of disdain and despair. “Right. Another job fair. I know about all the job fairs. For almost a year I’ve been going to every one I can find, standing in lines that stretch for miles. Finally, I got this job. And I’d still have it, except for this.” Dozier was pointing at the police form, the one that showed her arrest. Her eyes were wet. Her jaw was no longer holding firm. She turned and walked down the hall and out of the office.

“I’m sorry,” I said to her back, the useless words serving as final proof of my inadequacy.

Now I wanted to cry. It wasn’t an unusual feeling during my years as a public defender; sometimes the only thing that stopped the tears was another case or client that needed me right there and then. And so it was on duty day. I don’t remember who came in after Dozier, but there was invariably a line of clients in the waiting room, not to mention calls to be returned.

Duty day finally came to an end, and as I set about straightening up my desk, I noticed that Dozier had accidentally left a small stack of papers behind. On top was the printout from the courthouse. Underneath was a letter of commendation from sometime in high school when she had been intern of the month during a summer job with the DC government. The last piece of paper was a photocopy of her diploma – she had graduated from Ballou high school in south-east DC, a school more often in the news for fights or disorder than for anything good.

I started at the letter and the diploma, and I imagined she had brought them for the same reason she had told the officer who stopped her that she had a job. They were her armour, her stereotype-busters, her proof to the world that she was one of the good ones. I imagined her taking them with her to job fairs, to FedEx, to anyone she thought might have any power.

And I hated the futility of her effort. A just world would care that she had grown up in a neighbourhood with few jobs, attended a school with a 50% dropout rate, lost family members to prison and violence, yet had resisted and transcended all that. A just world would label her an achiever, a striver, a person with grit. But her strength of character, her diploma, her intern of the month certificate – none of it mattered now. What governed her life was a single line on a superior-court printout: “Sandra Dozier, DOB: 7/3/77, Arrest: Possession Controlled Substance (Marijuana), 2/15/00.”

Dozier had become the victim of the latest pretext-stop strategy. Designed to get guns off the street, it required casting a wide net – wide enough to capture lots of minor offenders, like Dozier with her two baggies of marijuana. Yet even this was only part of the problem. This policing strategy was reserved for the city’s black neighbourhoods – and its poorest. As a result, its burdens fell on residents who, like Dozier, could least afford the consequences of an arrest.

Why had a majority-black city instituted a style of policing that imposed such costs on its most disadvantaged residents?

On 13 January 1995, a racially diverse audience of more than 1,000 people crowded into the main ballroom at the Sheraton hotel in Arlington, Virginia, for a celebration honouring the memory of Martin Luther King Jr. The featured speaker, Eric Holder, was the first African American to serve as US attorney for the District of Columbia. (He would go on to become the nation’s first African American attorney general.)

As Holder took the stage, DC had emerged from the worst of the crack-cocaine epidemic, but just barely. Though homicide and other violent crimes had fallen from the record levels they had reached in those years, they were still extraordinarily high: DC’s murder rate was almost three times what it had been in 1985, before the crack explosion. The risk was greatest for the city’s black residents, as it was for black people nationally.

Using a conceit common among King Day speakers, Holder asked the enormous audience to imagine what King would think about the state of black America at the time. According to Holder, “Dr King would be shocked and disheartened by the condition of his people in 1995 – and I, for one, would be ashamed to reveal to him what we have let happen to our community.” He asked the audience to join him in a community-wide effort against gun violence. Tougher law enforcement alone wouldn’t be enough, Holder said, telling the crowd that he wanted to enlist athletes and musicians in a public relations campaign to “break our young people’s fascination with guns”. But while Holder embraced root-cause responses to violence – in 1994 he told the DC radio journalist Derek McGinty that “if we want to get a handle on this problem long-term, we’re going to have to deal with the social conditions that breed crime” – such broader solutions were beyond his direct control and would take years to show an impact. Meanwhile, people were dying.

Reducing violence in the short term, said Holder, required getting guns out of the hands of those most likely to use them to commit crimes – primarily young black men. But the means for disarming these potential offenders were limited. DC already had some of the nation’s toughest gun laws, and national legislation remained politically impossible. What was left? Holder’s answer was straightforward: stop cars, search cars, seize guns. He called it Operation Ceasefire.

In embracing investigatory stops, Holder was part of a movement. In a much-discussed opinion piece in the New York Times in March 1994, the prominent criminologist James Q Wilson had argued that police should conduct more pretext stops of pedestrians and frisk them in order to detect illegal guns. The practice would have costs, Wilson admitted: “Innocent people will be stopped. Young black and Hispanic men will probably be stopped more often than older white Anglo males or women of any race. But if we are serious about reducing drive-by shootings, fatal gang wars and lethal quarrels in public places, we must get illegal guns off the street.” The same year, the New York police department adopted a strategy similar to the one Wilson had proposed. In a document titled Getting Guns Off the Streets of New York, the NYPD detailed its aggressive strategy of stopping, questioning and frisking more citizens, especially young men of colour.

Facebook Twitter Pinterest Eric Holder in 2014. Photograph: Pablo Martinez Monsivais/AP

Holder wanted to do to drivers what Wilson and the NYPD sought to do to pedestrians. Under his proposal, teams of DC officers would be trained and equipped to look for vehicles they deemed suspicious, with the goal of searching them for guns whenever possible. Prosecutors would then back up the police effort by vigorously pressing charges in court, making sure the cases didn’t get dropped or fall through the cracks, and seeking jail time for those convicted of illegal gun possession.

Pretext traffic stops were an attractive tool for Holder’s purposes because DC, like every other city, has a dizzying number of traffic regulations, and most drivers violate at least one every time they get behind the wheel. A broken rear light or vent window, too much tint on the windows, a rear licence plate but no front one, or even too many air fresheners hanging from the rearview mirror – these are all valid reasons for a traffic stop. Thus, if a car draws suspicion from the police, they can almost invariably find a way to stop it legally. And once they do, they have broad powers, granted by the courts, to look inside the car, and then to ask the driver to allow them to search it.

In the days following his King Day speech, Holder appeared on radio talk shows and elsewhere to seek public support for Operation Ceasefire. Although he was remarkably forthright in laying out the elements of his plan, there were two aspects he failed to emphasise. First, he didn’t discuss the immense volume of innocent people who would have to be stopped in order to obtain a sizable number of guns. This volume of stops is necessary because the overwhelming majority of cars the police stop and search won’t contain guns.

Second, Holder failed to mention that although relatively few cars will contain guns, many more will contain evidence of minor crimes such as possession of marijuana. Police are sworn to enforce the law, and although it is theoretically possible to imagine a programme in which police seize guns but ignore other minor offences, it would be extremely difficult to execute. Among other obstacles, officers would need to be trained on which minor offences to overlook, and few police chiefs would be eager to attend a public oversight hearing at which they were forced to explain where they got the authority to decide which laws mattered. As a result, pretext-stop regimes invariably operate as Operation Ceasefire did. Officers may start out with a particular goal, such as seizing illegal guns, but if they uncover other illegal items, even less serious ones, they typically arrest.

But not everybody was at equal risk. In DC, one police district was officially exempt from Operation Ceasefire: the city’s Second District, which included middle- and upper-middle-class white neighbourhoods. The exemption was intentional. The Second District, Holder explained, had almost no gun crime, so there was no need for pretext stops there.

Holder’s explanation was entirely rational. In 1993, two years before Operation Ceasefire went into effect, there were 399 homicides in DC. Only two of them were in Ward 3 (which largely covers the Second District), despite the fact that this ward contained more than 13% of the city’s population. In one respect, though, the exemption of the Second District was problematic. By concentrating pretext policing in the areas where gun crime was highest, Operation Ceasefire created unwarranted disparities in drug enforcement. Drivers in majority-black neighbourhoods were no more likely to possess drugs than were drivers in majority-white neighbourhoods, but under Holder’s plan, they were more likely to be stopped, searched and arrested. These drivers – including Dozier – were the collateral damage from Operation Ceasefire’s response to gun violence.

There are a lot of Sandra Doziers. In the 20 years since Holder unveiled Operation Ceasefire, its brand of pretext stops has become part of the fabric of policing in cities across the US. In DC, the journalist David Shipler rode with officers doing the same things the police were doing the night they stopped Dozier: working the city’s poor black neighbourhoods exclusively, pulling people over for minor traffic violations (tinted windows remain a favourite) and cajoling their way inside cars.

The problem is hardly limited to DC. The NYPD came under sustained political and legal attack for its reliance on “stop and frisk”, a tactic we might think of as Operation Ceasefire applied to pedestrians. Although the NYPD has dramatically reduced its use of stop and frisk since 2011, it continues to target drivers for minor traffic offences. And it does so for the same reason that DC police adopted Operation Ceasefire: as a pretext to question drivers and, whenever possible, search their cars. In 2014, for example, the NYPD conducted just over 47,000 stop and frisks; in the same year, it gave out almost 75,000 traffic tickets for tinted windows alone. And that number is probably dwarfed by the number of drivers who, like Dozier, were stopped on suspicion of a minor offence and never received a ticket.

Pretext stops are responsible for most of the racial disparity in traffic stops in the US. Analysing the results of a survey of black and white drivers in the Kansas City area, political scientist Charles Epp found that when the police are actually enforcing traffic safety laws, they tend to do so without regard to race. But when they are carrying out investigatory or pretext stops, they are much more likely to stop black and other minority drivers: black people are about two-and-a-half times more likely to be pulled over for pretext stops. Moreover, the disparities are present regardless of gender. Black men are more than twice as likely as white men, and black women are more than twice as likely as white women, to be subjected to a pretext stop. In fact, black women are more likely to be pulled over for pretext stops than are white men, despite the fact that white men carry guns and commit violent crimes at much higher rates than black women do.

These racial disparities are all the more troubling because the damage from a pretext stop – of a driver, a pedestrian, a loiterer – doesn’t end with the stop itself or the subsequent search. Perhaps the single most destructive aspect of the pretext-stop regime is that it propels disparities in the rest of the criminal justice system. Consider Dozier. She wasn’t innocent: at the time she was arrested, possession of even the smallest amount of marijuana was a crime in DC. She had marijuana in her car, and she was arrested for it. Case closed. This is where many discussions of disparities in law enforcement end. But such a simple account fails to acknowledge the world that pretext stops create – a world in which Dozier is arrested for an offence that white drivers commit with impunity.

Before she left my office, after seeing that I couldn’t help her get her job back, Dozier said: “I can’t believe I lost my job for this.” I still can’t believe it myself, but I now have a better understanding of how it happened. By the time Dozier was stopped and received her marijuana citation in 2000, we had been steadily, incrementally, building the punitive criminal justice system we still live with today. Most of the pieces – the aggressive prosecutions and policing, longer sentences, prison-building, collateral consequences of convictions such as losing the right to vote or the chance to live in public housing – had been put in place, and the years since had been primarily dedicated to maintaining and tinkering with that basic architecture.

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This history reveals that no single actor, or even institution, is responsible for what happened to Sandra Dozier. But it also suggests that there were many moments when DC – and the nation – could have pursued a different course. If the city council had chosen to decriminalise marijuana, Dozier would still have had her job. If the police hadn’t targeted drivers in the city’s poor black neighbourhoods for pretext stops, she would still have had her job. If FedEx and other employers had a more forgiving policy toward arrests, or if they were willing to look at individual circumstances rather than adopting a policy of blanket exclusion, she would still have had her job. And if the US had implemented a more robust policy of urban revitalisation – if it had ever undertaken a Marshall plan for the cities – somebody with Dozier’s grit and determination would have had her choice of jobs.

This is an extract from Locking Up Our Own: Crime and Punishment in Black America by James Forman Jr, published by Little Brown and available at guardianbookshop.com

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