At his confirmation hearing, Sen. Jeff Sessions testified that he reveres the Constitution and is committed to the rule of law. If he intends to fulfill the Justice Department’s obligation to ensure that police officers also adhere to the rule of law, he must rethink his skepticism of the DOJ’s single-most important tool to reform troubled police departments: consent decrees. Earlier this month, the department’s Civil Rights Division completed a 13-month investigation that found a long-entrenched pattern of unlawful force in the Chicago Police Department. The probe found that the behavior persisted despite decades of reform efforts and may be contributing to Chicago’s spiraling murder rate. To its credit, Chicago agreed to a consent decree — a court-enforced agreement with DOJ — to improve its police force. Things are at last looking up for those who support lawful and effective policing in Chicago, but only if Sessions is willing to learn from the DOJ career attorneys who can show him how crucial consent decrees are. The Justice Department is currently enforcing 14 consent decrees aimed at eliminating unlawful conduct it found in local law enforcement agencies. While these agreements are few in number and continue to evolve and improve, there is no question that they have played an indispensable role in improving police adherence to the rule of law and repairing broken police-community relationships. Police departments where consent decrees have already been fully implemented provide one indication of their value. An independent study of the Los Angeles Police Department consent decree found it resulted in broad improvements, including meaningful reform of police practices and increased trust among the public. And, to allay Sessions’ concerns that consent decrees harm officer morale, it’s worth noting that LAPD officers had greater job satisfaction after the consent decree was implemented. An academic analysis of police departments in Los Angeles, Cincinnati, and Pittsburgh found that mandated reforms are likely to result in police departments with more effective accountability infrastructure, better training, and policies that reflect policing best practices. Less formal analyses are equally compelling. Detroit for instance, found that officer-involved shootings dropped from 47 in the five-year period before its consent decree to 17 in the five-year period after. All these studies are outlined in a recent Civil Rights Division report. A newer generation of consent decrees is just beginning to have a broad impact, but indications are these will be even more successful in bringing about constitutional policing and repairing police-community fissures. Periodic surveys in Seattle required by its consent decree show increasing public confidence in policing. The latest showed all-time high numbers of African Americans and Latinos approving of treatment by police during stops. The long-troubled New Orleans Police Department has finally, under a consent decree, shown significant improvement. In just one example, that police department’s independent monitor reported a “significantly reformed” response to sexual assault and domestic violence that improved public trust. The result? An 83 percent increase in sexual assault reporting in 2015 alone. That’s quite a shift from the results of the first federal investigation of the New Orleans police department over a decade ago. In that investigation, as in the first investigation of Cleveland’s police department, the Justice Department did not insist upon a consent decree. Subsequent tragic deaths, including those on the Danziger Bridge in New Orleans and that of young Tamir Rice in Cleveland, delivered painful lessons. The Justice Department reinvestigated both police departments and, this time, all parties agreed to consent decrees. Consent decrees also serve as both beacons and touchstones that instigate broad positive change throughout policing. That’s crucial in a nation with more than 15,000 state and local law enforcement agencies — and only about 70 Department of Justice pattern-or-practice investigations in 20-plus years. While this broader impact is difficult to quantify, one can go anywhere in this country and see it’s real. During the six years I spent investigating police departments and negotiating consent decrees for the Justice Department’s Civil Rights Division, I cannot remember attending any gathering related to policing when I wasn’t approached by someone from a place the Justice Department had never investigated and probably never would who still said consent decrees had improved policing in their city. There was the earnest lieutenant eager to tell me of changes that his department made to training and use-of-force reporting; the community leader who told me how he and others had convinced town officials to change the way fines and fees are collected after pointing them to our Ferguson consent decree; the sergeant telling me she’d “read every one” of our consent decrees and kept her chief apprised to ensure their department had mechanisms to detect and respond to incidents of officer misconduct. Law enforcement officials sometimes sent me new policies and trainings revised after reviewing our consent decrees. Justice Department police consent decrees, created with input from national police experts, local police officers and interested community members (and affirmed by local legislatures) inspire the creation of best practices that can be implemented to restore police legitimacy and avoid the tragic incidents that have roiled too many communities the past several years. Consider how New Orleans, required by its consent decree to provide peer-intervention training to officers, responded by creating its EPIC program to teach officers how to step in and prevent excessive force and other police misconduct before it occurs. That program is now poised to become a national model. The Constitution doesn’t require that a city or town have a police department. It does require that if a community chooses to give a small group of people the tremendous authority to take away life and liberty, the entrusted individuals must exercise that authority consistent with the rule of law. For the sake of our democracy, let’s hope that Sessions can see that sometimes fulfilling this fundamental constitutional principle requires a consent decree. Christy E. Lopez is a Distinguished Visitor from Practice at Georgetown Law. From 2010-2017 she was a Deputy Chief of the Special Litigation Section of the U.S. Department of Justice's Civil Rights Division, where she headed the section’s Police Practice group and oversaw the investigations of the Chicago, Ferguson, and New Orleans police departments, among others. She has been working on police reform issues for more than 20 years, including serving twice with the Department of Justice's Civil Rights Division.