[Editor’s note: On Tuesday, President Trump fired FBI James Comey, stating in his letter to Comey that he had accepted the recommendation of Attorney General and Deputy Attorney General that Comey was “no longer able to effectively lead the Bureau.”

In a memo released publicly along with that letter, Deputy Attorney General Rod J. Rosenstein laid out the case for Comey’s dismissal. Writing to his boss, Attorney General Jeff Sessions, Rosenstein focused on “the Director’s handling of the conclusion of the investigation of Secretary Clinton’s emails.”

Rosenstein made several criticisms of Comey’s conduct. First, he criticized the decision to announce, on July 5, 2016, that the investigation was closed — saying that this amounted to a usurpation of the authority of then–Attorney General Loretta Lynch. He then said Comey compounded his error by holding a press conference in which he released “derogatory information” about Clinton — contrary to FBI practice. Rosenstein similarly criticized Comey for publicly announcing, on October 28, that the Clinton investigation was not closed after all.

Who is Rod Rosenstein? In a recent piece for Vox, Thiru Vignarajah, a lawyer who worked for Rosenstein at the US Attorney’s Office in Maryland, argued that Rosenstein had a vision of law enforcement that greatly differed from that of Jeff Sessions. As the merits of Comey’s dismissal are debated, Rosenstein’s ideology and credibility will surely come under close scrutiny.]

The United States Senate just confirmed Rod Rosenstein as the country’s Deputy Attorney General, ending his tenure as US Attorney for Maryland after a dozen years of distinguished service. The first order of business for Rosenstein may be briefing his new boss, Attorney General Jeff Sessions, on how Maryland reduced violent crime rates by 37 percent from 2005 to 2014 — because it was not by following the script that Sessions has been promoting.

When it comes to fighting crime, Sessions seems to be dusting off the failed playbook of the 1980s. He is concerned that America has developed “too much of a tolerance for drug use — psychologically, politically, morally.” Because “lives are at stake,” he recently said, he is “not going to worry about being fashionable.” No risk of that. From hitting the brakes on police reform, to praising Nancy Reagan’s “Just Say No” campaign, to stressing the supposed moral failings of drug users, the attorney general has signaled a return to the policies and rhetoric of zero tolerance, dragnet deportation, mandatory minimums, and mass incarceration as the backbone of the Justice Department’s strategy to curb violent crime — which Sessions likes to say is on the rise.

In truth, crime nationally remains at historic lows. Unfortunately, some cities like Baltimore have seen a heartbreaking surge in murders and violence after years of steady progress. But that progress was not achieved by resorting to the tactics that Sessions appears to support.

Rosenstein enjoyed rare bipartisan support in Maryland and was the only United States attorney in the country appointed by President George W. Bush who remained in the role at the end of the Obama administration. This was no accident. Federal prosecutors who served in his office (Democrats like me among them) wrote in support of his confirmation, and local elected prosecutors from across Maryland sent the Senate a similar letter, reporting that when they ask Rosenstein for assistance, “he does not care if you are a ‘D’ or an ‘R’, he has only cared about making this State safer.”

And there he made real strides. Over his first decade as the lead federal prosecutor in Maryland, murders statewide were cut by a third, double the decline at the national level. Other violent offenses like robberies and aggravated assaults also fell faster than the national average, including a remarkable 70 percent drop in carjackings across the state. A few years ago, even in the stubborn conditions of Baltimore, Rosenstein — working shoulder-to-shoulder with law enforcement, state, and local prosecutors, and most important the community — saw bleak homicide numbers decrease to less than 200 for the first time in 33 years.

A lot of folks deserve credit for that, as Rosenstein would be the first to point out. But he was a big part of it. Take, for example, the impact on the Cherry Hill community in South Baltimore, where there had been 35 shootings in one year soon after Rosenstein took office. In 2013, his office brought federal racketeering charges against 26 men responsible for numerous murders, shootings, and robberies. Afterward, the neighborhood went 700 days without a shooting.

That was tough, targeted enforcement, and it was typical of his tenure. Prosecutors helped drive down murder and violent crime rates by concentrating on gang leaders and gun violations, not by vilifying victims of addiction, getting tough on marijuana, or reviving policies of mass incarceration for petty offenses. Collaboration between prosecutors, police, and the community combined with a dogged focus on violent repeat offenders was the anchor of Rosenstein’s approach.

In addition, reconceiving America’s drug epidemic as a public health crisis, not solely as a problem of crime, has represented a massive step forward in policy and insight — one that Rosenstein embraced. Last year, in an editorial in the Baltimore Sun, he and Maryland’s Attorney General Brian Frosh described the heroin and opioid epidemic as “one of the most significant public health issues facing the nation.” Even as they promised to seek stiffer penalties for dealers whose drugs led to overdose deaths, they also concluded: “Enforcement efforts are more effective when they are part of a larger strategy to prevent addiction by educating potential drug abusers, and ensuring that help is available to people who become addicted.”

Sessions does not seem convinced. Last month, at a youth summit, the attorney general talked up enforcement and appeared to disparage treatment, remarking that it “often comes too late” and that he had “seen families spend all their savings and retirement money on treatment programs for their children, just to see these programs sometimes fail.” Complete remission among victims of heroin addiction will never be 100 percent, but that has not stopped Rosenstein from appreciating the importance of treatment, particularly in the context of reentry programs.

A year ago, Rosenstein visited a federal prison to talk with inmates about their future. He recognized that they “face strong temptations to return to a life of crime” and emphasized the programs available to help them, saying, “Our mission is preventing crime, not just sending people to prison.” Rosenstein hired a re-entry specialist and this past December published a statewide 181-page catalog of services for ex-offenders seeking a better life. The funds from the Justice Department that made this possible are now on a list of cuts Sessions reportedly wants to make.

Sessions has also blamed immigrants for everything from DUIs to rapes to gang murders, warning that “countless loved ones would not be grieving today if the policies of sanctuary jurisdictions were ended.” But mass deportation is no better a strategy to identify and incapacitate violent criminals than mass incarceration was to fight the spread of drugs in America’s inner cities. Rosenstein seems to get that too. Following the directive of President Barack Obama to prioritize “felons, not families … criminals, not children,” Rosenstein sparingly used federal immigration laws to target violent repeat offenders who were breezing through the state system.

A prosecution of mine, for example, resulted in the incarceration of a domestic abuser for violating federal immigration law: He had twice entered the country unlawfully, twice attacked his victim, and twice pled guilty to assault. The second attack — where he started to beat and strangle his victim before throwing her to the ground — took place back in Baltimore just months after he had been deported.

Beyond individual cases like this where special attention is warranted, Rosenstein has also consistently gone after whole organizations like MS-13, bringing his first indictment against 19 members of the vicious street gang in his first year as US Attorney and his last one just last month. He would notify immigration officials of criminal defendants who were in the country unlawfully. But his first priority was holding them accountable for the murders and violent crimes they committed in Maryland.

Nor did Rosenstein ever doubt the need to crack down on police misconduct. As US attorney, Rosenstein prosecuted individual cases of corrupt cops across the state. For years, he also pursued sweeping indictments that exposed systemic wrongdoing by law enforcement. They ranged from extortion charges in 2011 against city officers who, for a kickback, funneled accident victims to select towing operators, to a racketeering conspiracy in 2013 involving prison guards who were in bed with inmates (literally and figuratively). Currently pending are allegations against seven police officers accused of falsifying arrests and stealing money and drugs from arrestees.

Thanks to careful, painstaking investigations like these, Rosenstein has managed to preserve excellent relations with local law enforcement while at the same time bringing corrupt officials to justice. These cases also sent an important, unmistakable signal to the community that wearing a badge is not a license to break the law.

No one disputes that Rod Rosenstein is a rock-ribbed Republican. But he had an impact in Maryland using strategies and rhetoric very different from those Sessions has espoused. What has happened in Baltimore the past two years is wrenching and tragic, but the answer is not to disregard the lessons from the decade of progress Rosenstein embodied.

The attorney general would be wrong to sideline the very strategy that made his new deputy such a success. It would also dishonor the work of police and prosecutors at the state and federal level who toiled for a decade — led by dedicated public servants like Rosenstein — to prove that we can secure public safety without sacrificing our values.

Thiru Vignarajah, who previously served as deputy attorney general of Maryland and as law clerk to Judge Guido Calabresi and Justice Stephen Breyer, began his career as a federal prosecutor under Rod Rosenstein at the US Attorney’s Office in Maryland before serving as a city prosecutor in Baltimore. He is now a partner at a global law firm; the views here are his alone. Twitter: @tvignarajah.

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