Three dozen sheriff’s officers and Metropolitan Transit System security officers board the trolley as it pulls into Lemon Grove station. They go car to car, person to person, checking that everyone paid a fare.

If you don’t have one, you’re asked to step off the train for more questioning. In the next few hours, they’ll write a bunch of citations, but the Sheriff’s Department isn’t actually concerned with $2.50 fares.

Its four-month “Operation Lemon Drop” was really about targeting a handful of the county’s 1,175 ex-inmates released from prison under realignment without parole or probation requirements— “the worst of the worst,” as Commander Dave Myers calls them.

The department combs available information to determine which ex-inmates are “prolific offenders” and sets up dragnets in public places they might pass through, like the Lemon Grove trolley station.

It’s an example of intelligence-led policing — analyzing data to direct police resources — but it’s also a major part of the county’s response to realignment, the 2011 law that shifted the burden of incarcerating low-level felons from the state to counties.

The idea is to identify people likely to commit serious crimes, and create an opportunity to arrest them for something else before that happens.

“Let’s say I’m a gangster who likes to steal cars and I’ve done armed robberies before, but on this day I’m just in possession of meth,” Myers said. “I’m going to use that against them. I’m going to arrest them, go after them and use their vulnerability because I know they’re a drug user or something, and I’ve probably prevented another robbery, another stolen car or something like that. That’s kind of the basic formula.”

But the effort to track and target people who’ve been released from jail raises concerns in concept and in practice. There’s the creepy “Minority Report”-esque “pre-crime” element. Plus, Operation Lemon Drop’s final numbers show that only 1 percent of people contacted by law enforcement were ultimately arrested, including some for misdemeanors.

And while the Sheriff’s Department says it’s using data to identify likely offenders, what if the guy with a joint in his pocket is just a guy with a joint in his pocket, not a future violent criminal at all?

Realignment created a specific group of ex-inmates released without “a tail,” meaning parole or probation – arrangements that allow law enforcement to screen released inmates for drugs, search their homes and otherwise monitor their behavior.

So the department uses government databases to reverse-engineer a tail. That’s the basis for Operation Lemon Drop. Checking for fares and other nuisance infractions on the trolley is just a reason for officers to establish contact for further questioning.

“Seventy percent of crimes are committed by repeat criminals,” Myers said. “That’s the state’s own statistic. So that’s who we’re targeting. We’re actually looking to prevent crimes. I mean, in theory, if this all works — and I think it does — we’re actually preventing crimes from happening.”

Steven Zeidman, director of the criminal defense clinic at the CUNY School of Law, wonders whether targeting inmates released under realignment cuts against the spirit of the law in the first place.

“You have an officer who says let’s go after the ‘worst of worst,’” he said. “Well if that’s what they are, why are they out? Someone has made a determination that they should be released without stipulation.”

Information-led policing is common nationwide, with many touting it as an effective way to reduce crime, but San Diego’s use of data to track inmates released under realignment is one of a kind, said Myers and Robert Weisberg, co-director of the Stanford Criminal Justice Center, which tracks local responses to realignment.

By using fare violations to generate probable cause, the operation also borrows from the so-called broken windows theory, made famous in early ‘90s New York City. Cracking down on minor crimes, the theory goes, prevents more serious crimes from happening. Its application spawned New York’s controversial “stop and frisk” policy, which was eventually killed off.

“This is a modernization of early ’90s policing,” Weisberg said. “You’ve got (information-led policing) mixed with broken windows, and it’s also a creative and enabling way of putting people under supervision even if realignment made them bereft of supervision.”

Myers says efforts like Operation Lemon Drop are part of why the county’s crime rate is declining.

But the sort of massive show of force that results from 30-plus officers taking over a public place isn’t always a great way to build trust between law enforcement and communities in which they operate.

Not to mention, Operation Lemon Drop’s final stats raise questions about its overall efficacy.

During its five days, from July through October, the department contacted 16,631 residents during the operation. Usually a “contact” meant asking for proof of fare.

From that, officers pulled aside 624 people for further questioning and issued 451 citations. But it turned up just 186 misdemeanor or felony arrests, or a total of 1.1 percent of the people contacted by an officer throughout the operation.

The bottom line: Thousands of citizens were stopped by law enforcement in order to arrest fewer than 200 people, including some for simple misdemeanor offenses.

“If there are 180 cases or arrests out of 16,000 people contacted, at what point do we talk about efficacy, that you can point to some 10 or 20 specific arrests and say this justifies all that you’ve done?” said Zeidman, who worked as a public defender in New York during the dawn of the city’s broken windows efforts.

“It raises all kinds of red flags,” he said. “You give departments all the credit in the world when they marshal their resources and innovate. But we need to step back and say, ‘This will have a disproportionate impact in some communities.”

In other words, when does smart policing become a police state?

Born Out of Realignment

Prison populations exploded all over the country through the 1990s, but things were even worse in California, where a third felony sent a criminal to prison for life.

In 2011, a federal judge ruled prison overcrowding violated inmates’ civil rights. The state Legislature passed a law that kept serious offenders in state prisons but transferred the responsibility to incarcerate, supervise and rehabilitate low-level offenders to the counties.

The move was intended to put the cost of incarceration on the same people making decisions about whom to arrest and how to charge them, Weisberg said.

“The people who really control who goes to prison are police and prosecutors,” Weisberg said. “Turns out, it’s mostly a result of prosecutorial discretion, rather than crime rates.”

Together, San Diego’s law enforcement agencies created the regional realignment intelligence unit, a group that does data analysis on ex-inmates and provides the results to each agency.

Law enforcement refers to the group of ex-inmates tracked in Operation Lemon Drop as “1170s,” based on the section of the realignment law. They’re non-violent, non-sexual, non-serious offenders who would have still been in prison if not for realignment and have no formal government supervision.

“How do we in law enforcement ensure that 1170s that don’t have a tail are doing or being what or where they’re supposed to be?” Myers said. “How do we ensure those people that are in our neighborhoods, that we all have a stake in, ensuring that they’re successful, and how do we share information if they’re not being successful, because that leads to quality-of-life issues that affect communities, which is: crime.”

How It Works

The data analysts comb for clues in available information — gang affiliation, prior arrest records, DMV files, any information from traffic stops or other police interactions that didn’t lead to an arrest, prior probation records, anything at their disposal.

In the case of Lemon Drop, that meant checking against factors like “suspected gang association,” whether they’ve ever had a police interaction in a specific area or prior arrests for burglary or robbery.

If an ex-inmate checks enough of those boxes, he or she is categorized as a “prolific offender.”

Analysts then look for connections between all the prolific offenders and their known associates to create a “link chart” that looks something like a family tree. Myers says it’s a simple visualization of an active criminal network.

Then they draw a circle around the area on the map they all have in common.

That brought them to Lemon Grove.

The department then monitored their public social media feeds and found they all spent a lot of time on the trolley. They decided the Lemon Grove trolley stop would be a good place to intercept them.

During the operation, a few sheriff’s officers would join a few dozen security personnel from Metropolitan Transit System, the group that operates the trolley, and a few probation officers.

For four or five hours, they’d pull aside anyone who didn’t have a proof of fare, as well as anyone else who gave them probable cause in some other way, like playing music too loudly, being visually intoxicated, or if officers saw a person they knew to be on probation.

Evaluating Success

To Myers, Operation Lemon Drop and operations like it aren’t just successful — they demonstrate San Diego’s forward thinking on one of California’s biggest issues.

In his inauguration last week, Sheriff Bill Gore said San Diego County has responded to realignment better than the rest of the state, all because of information-led policing.

But out of the 186 people arrested throughout Operation Lemon Drop, the department couldn’t say how many are actually those 1170s it was targeting, despite that being the basis of the program. It said at least 20 were on probation or parole.

Myers said the program’s success should be based on the county’s crime rate.

Indeed, the rates of property crime and violent crime are trending downward, according to mid-year 2014 statistics.

“It’s about crime reduction in the first place,” Myers said. “The (ex-inmates) really are a starting point for tracking repeat offenders. That leads us to the right people and their networks so that we can prevent crime instead of responding to crime.”

But the state’s crime rates are on an overall decline too. San Diego is alone in using data to target the non-serious offenders released under realignment.

“Let’s say they find a guy with a joint,” said Joshua Chanin, a San Diego State University professor of public affairs who studies policing strategies. “He’s breaking the law. But it’s a matter of whether you’re concerned with that, or other things.”

That’s where prevention comes in, as far as Myers is concerned.

He trusts the data, and the data says the Lemon Grove station is a hotspot of criminal activity.

Collateral Effects

An armed police presence in a public place is bound to have an effect on that community, particularly when the data consistently points operations to certain low-income neighborhoods, like Lemon Grove.

Myers said he’s sensitive to those concerns.

“There are those who might feel this is an infringement on their rights,” he said. “And I totally get that, and I think we continue to have a conversation about why they feel that way. I mean, if you paid your fare, if you’re not doing anything criminal in nature, the conversation with us is going to be very short.”

People from the neighborhood often thank him for being there during operations, Myers said.

Lavondren Price, a 21-year-old who lives near the 62nd Street station, wasn’t one of them. Price works at the Food 4 Less near the Euclid Avenue station and often visits friends at the nearby Lemon Grove station. He doesn’t have a car, so he rides the trolley a lot.

In November 2013, he was on the trolley without having paid a fare when it pulled into Lemon Grove and a swarm of officers boarded the train.

Price had his headphones on and walked past an officer who said he’d ignored a request to show his fare.

He wasn’t just given a ticket for fare violation. He was cuffed and sat on the curb with five other people, asked if he was on probation, if he’d ever been convicted of a crime, where he was going.

“I could look to my left and see everyone in cuffs was a black male and under 21,” he said. “I said, ‘You all are targeting someone out here.’ I have no kind of record.”

Forty minutes later, he said, he was given his citation and sent on his way. But he says that sort of presence is common around the stations, and he often sees young people asked about their criminal history, or if they’re in a gang.

The local ACLU said some residents have reported being asked what gang they’re in, or where they were the previous night.

All those questions fuel a vicious cycle, Zeidman said. Having an operation in a certain neighborhood makes future ones there more likely, since local residents’ information is fed into the database used to identify prolific offenders.

“It’s self-perpetuating,” he said. “It’s, ‘We’re going to police in areas we want to police, and now we’re going to justify it.’ Everyone is going into databases, and everyone is followed once they’re in them, and you have to ask how did they get in them in the first place and what are the criteria?”

Disproportionately, he said, they’re filled with minorities and people living in low-income areas brought up on minor offenses.

San Diego’s ACLU jumped on that concern too, saying the operation appears “race-based.”

It’s since held “know your rights” awareness campaigns at the station, informing residents when they don’t need to submit to officer questioning.

“In July, an ACLU staff member who lives in Lemon Grove … ran head-on into what looked like a military operation that would have befitted the apprehension of a terrorist,” Christina Griffin, an ACLU organizer, said in a statement. “There were police and sheriff’s cars surrounding the Lemon Grove trolley station and what appeared to be about 70 police, sheriff and MTS officers, some in what looked like riot gear.”

Griffin said the staffer grew concerned when officers declined to stop her, and believed it was because she was a white woman.

“The qualifiers of when to ask riders if they are on parole or probation and whether this is based on race is very concerning,” Griffin said.

Myers strongly rejected the allegation.

He said that the department has held similar information-led operations in Encinitas, Poway, Santee, El Cajon, La Mesa and on the Sprinter in North County.

“The whole idea that this is race-based is outrageous and completely without basis,” he said. “We don’t control the demographics of communities where the data leads us.”

Correction: An earlier version of this story misstated the circumstances under which ex-inmates tracked by Operation Lemon Drop were released. They were released without probation or parole requirements they would have had prior to realignment.