Ranjana Natarajan is a clinical professor and director of the Civil Rights Clinic at The University of Texas School of Law.

Racial profiling and use of excessive force are destroying public confidence in law enforcement. (Stephen Lam/Reuters)

The #BlackLivesMatter movement has sparked nationwide protests and has raised awareness worldwide about the unequal treatment of black people by police in the United States.

Listening to the voices from the movement — and learning from the death of Eric Garner and the series of other deaths of unarmed black men — it’s clear that two issues need to be addressed: racial profiling and police use of excessive force. Both run afoul of the U.S. Constitution, but remain common practices in law enforcement, too often with tragic results.

In Garner’s case, for example, police targeted him for the petty crime of selling loose cigarettes — the types of crimes black people are targeted for at higher rates — and then attempted to arrest him with a chokehold, banned by the department. Whatever else we have learned from the recent tragedies of police violence, it is clear that we need comprehensive federal, state  and local policies that outlaw racial profiling and rein in police excessive force.

Racial profiling — as well as profiling based on religion, ethnicity and national origin — continues to plague our nation despite the constitutional guarantee of equal treatment under the law. In a 2011 report, the Leadership Conference on Civil Rights found evidence of widespread racial profiling, showing that African Americans and Hispanics are disproportionately likely to be stopped and searched by police, even though they’re less likely to be found possessing contraband or committing a criminal act. In Illinois, for example, black and Hispanic drivers were twice as likely to be searched after a traffic stop compared to white drivers, but white drivers were twice as likely to have contraband. The NYPD’s controversial stop-and-frisk program shows similar evidence of racial profiling, with police targeting blacks and Latinos about 85 percent of the time. In nearly nine out of 10 searches, police find nothing.

Likewise, excessive force by police persists despite the Constitution’s prohibition on unreasonable searches and seizures. In lawsuits and investigations, the U.S. Department of Justice has concluded that a number of major police departments have engaged in a pattern or practice of excessive force. The Cleveland Police Department was most recently found to be an offender, but it follows a long line of other wayward law enforcement agencies: Seattle, New Orleans, Portland, Newark and Albuquerque among them. Clearly, cases like Eric Garner’s are not isolated — police use of excessive force is a systemic, national problem. The DOJ has recommended revising and clarifying local policies regarding appropriate uses of force, improving officer training and supervision, and implementing rigorous internal accountability systems, among other things. But recommendations are not enough. Conquering this systemic issue demands a national mandate.

Profiling undermines public safety and strains police-community trust. When law enforcement officers target residents based on race, religion or national origin rather than behavior, crime-fighting is less effective and community distrust of police grows. A study of the Los Angeles Police Department showed that minority communities that had been unfairly targeted in the past continue to experience greater mistrust and fear of police officers. To root out this ineffective tactic that undermines public confidence, we need stronger policies against racial profiling at all levels — from local to federal — as well as more effective training and oversight of police officers, and systems of accountability.

Twenty states have no laws prohibiting racial profiling by law enforcement, according to an NAACP report released in September.  Among states that do, the policies vary widely in implementation and effectiveness. Only 17 of those states require data collection on all police stops and searches, and only 15 require analysis and publication of other racial profiling data. Limited and inconsistent data collection makes it impossible to devise effective remedies for racial profiling.

Last week, the U.S. Department of Justice unveiled a newly revised guide on use of profiling by law enforcement, distinguishing between legitimate uses (such as using race and other characteristics in a suspect description) and illegitimate uses (such as criminal stereotypes). Among other things, the guide explains that uses of race and other characteristics should be based on particularized and trustworthy information relevant to the specific investigation, rather than generalized stereotypes. The policy also provides general provisions on training, data collection and accountability, and it was expanded to include national origin, religion, gender, sexual orientation and gender identity. Civil rights groups have been calling for this updated guide for years.

However, the Department of Justice did not address all concerns. Civil rights advocates had also called for the elimination of loopholes for national security and border enforcement, which the DOJ did not adopt. The document states:

This Guidance does not apply to Federal non-law enforcement personnel, including U.S. military, intelligence, or diplomatic personnel, and their activities. In addition, this Guidance does not apply to interdiction activities in the vicinity of the border, or to protective, inspection, or screening activities.

The DOJ policy, however, is far clearer and stronger than policies held by many states and localities. As the NAACP found, some states and localities ban the use of pretextual traffic stops, others explicitly prohibit racial profiling, and still others require mandatory data collection — but few contain all of the elements of an effective racial profiling ban, and many states lack profiling laws altogether. Since Americans encounter local police in far greater numbers than any federal law enforcement officers, the adoption of state and local laws and policies banning profiling is critical.

Excessive force and racial profiling are two destructive modes of police misconduct that require concerted, vigilant action to reduce and eliminate. While racial profiling can end in tragic police killings of unarmed individuals, such as with Eric Garner or Michael Brown, it also results in many unnecessary stops and searches, harassment and intimidation, and even confiscation of property without due process. The steps to curb this are clear: At all levels of government, we need definitive anti-profiling laws and policies, training of officers on the elimination of explicit and implicit bias, data collection on traffic stops and other police-community contacts, and development of internal and external accountability systems. With these efforts, police departments across the country can rebuild public trust and ensure that policing methods reinforce rather than undermine our democratic values.

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