Chuck Rosenberg

Opinion contributor

In my decades serving with the Justice Department, the FBI and the Drug Enforcement Administration, I learned that smart law enforcement is attuned to the needs of the communities it serves, and that it is flexible and nimble as needs change.

President Donald Trump’s approach to MS-13 is the opposite: inflexible and clumsy, based on stereotypes rather than facts. By constantly invoking the specter of MS-13 to rouse anti-immigrant sentiments, as he did Monday when he warned again that MS-13 was “pouring into our country,” he undermines law enforcement efforts.

MS-13 is a violent street gang that originated among Salvadorans in Southern California in the 1980s; it continues to be a destructive and destabilizing presence in El Salvador and Honduras. MS-13 members have committed horrific acts of violence around America, but the gang is concentrated in a few locations, including Los Angeles, Long Island and the Washington, D.C., area.

In those communities, it is a serious problem and an appropriate focus of law enforcement — a threat that requires significant investigative resources. In other communities, not so much. Reliable estimates show MS-13 has approximately 10,000 members in our country — sizable, but smaller than many other dangerous gangs.

Fight crime based on facts, not politics

These differences between communities are precisely why the FBI has more than 150 Violent Gang Task Forces spread around the country. Those task forces work with local officials to investigate and prosecute gang-related mayhem, including drug trafficking, racketeering, firearms violations and other violent crimes. The scourge of gang violence is not uniform, and local communities, in coordination with their federal partners, know best how to address local threats.

In Northern Virginia, local governments tend to be corruption-free. When I served as the U.S attorney for the Eastern District of Virginia, it would have made little sense to create a public corruption task force there. By contrast, in the 1990s, the Richmond Division of our U.S. Attorney’s Office spearheaded Project Exile — designed to lock up violent felons with guns — in a city then plagued by violent felons with guns. It worked, and violent crime rates dropped significantly in Richmond.

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MS-13 beat me up and threatened to kill me. Then the US government took my kids.

Law enforcement priorities should also vary from agency to agency, based upon mission. When I ran the DEA, our focus, and properly so, was on violent Mexican cartels and the unholy alliance they had formed with dangerous distribution networks in the USA. MS-13 is occasionally connected to these criminal networks, but often it is not. When Attorney General Jeff Sessions last yearasked the DEA to prioritize MS-13, I objected. I knew that MS-13 did not operate at nearly the same level as other violent transnational organizations that demanded DEA prioritization and focus. Given limited resources, facts must drive enforcement priorities and the allocation of scarce resources.

The president’s focus on MS-13 is political and undermines efforts to counter it. Former MS-13 members have warnedthat his constant references to the gang have given it visibility and free advertising, enabling it to recruit and metastasize.

Further, numerous studies demonstrate that immigrants commit crimes at lower rates than natural-born citizens. Undocumented immigrants who commit violent crimes need to be prosecuted and removed from the United States, but immigrants who seek legal admission and productive lives here must be welcomed. Our immigration debate must be decoupled from MS-13 fear-mongering.

Trump is undermining law enforcement

Oddly, despite the president’s tough-on-crime rhetoric, he consistently undermines the work of those charged with enforcing the law — the FBI and the Justice Department — by publicly trashing their efforts.

One risk of many is that law enforcement needs information to combat crime, and it often comes from those who live in afflicted communities. Victims and concerned citizens tend to know best who is doing what, where. Denigrating our law enforcement agencies erodes trust, which means folks who live in communities plagued by crime might be less likely to cooperate with law enforcement.

Remarkably (and relatedly), in an effort to protect his own interests, Trump recently opined that “flipping” ought to be illegal. I understand why he might not be too keen on that tactic, which prosecutors use to gather intelligence by turning one criminal against other criminals. But it is an important tool, and prohibiting it would have significant adverse consequences for law enforcement and its ability to protect public safety.

Ultimately, we need an honest assessment of the real threats to our communities, divorced from politics and rhetoric. That will look different in Chicago than it does in Memphis or Los Angeles. It may be public corruption in one place, felons with guns in a second place, and MS-13 in a third. One size may fit all in beach towels, but not in law enforcement.

Let’s discount unenlightened political voices and heed the more knowledgeable law enforcement voices close to home.

Chuck Rosenberg is a former U.S. attorney, senior FBI official and chief of the Drug Enforcement Administration.