By Michael J. Jenkins

Donald Trump was right last week when he noted that "stop and frisk" is not an unconstitutional practice. However, his persistence in positing it as his sole solution to urban violence - after all that has unfolded in policing over the past few years - demonstrates his ignorance of the crime and policing situation in our cities and in the "badly treated African American community."

In 1968, the U.S. Supreme Court decision of Terry v. Ohio authorized police, in the course of an investigatory stop and for their own safety, to frisk an individual whom they have reasonable suspicion to believe might be carrying a weapon.

In 2016, police can still stop a person suspected of committing a crime, to ask about his behavior, and, if the circumstances suggest it, frisk the individual for a gun. Even in New York City, where a federal court ruled the NYPD's application of stop and frisk unconstitutional, police still stop dozens of New Yorkers each day - presumably in a way that respects individual rights.

But Trump misses the mark - "big league," as he would say - when he suggests the stop-question-and-frisk practice should be employed carte blanche, with no regard for community expectations or the potential negative effect on police-community relations. As in many areas of Trump's platform, it appears he knows the history and wants to repeat it - recent police improvements and lessons be damned.

At the height of our country's violent crime wave in the mid-1990s, and amid a drastically different political and criminal justice environment, stop and frisk was used in a widespread fashion to help communities fight crime.

Given today's near-all-time-low crime rates, new research on police efficacy, emerging technological capabilities, and shifting community standards, cities require a more refined method of policing. The field of policing has changed, and so too must the approaches they take in urban neighborhoods.

There is greater accountability for police. For example, prosecutions of police involved in the killing of a citizen in the line of duty have tripled. The focus on procedural justice and police legitimacy today is as important as crime reduction.

Urban police forces emphasize getting buy-in from communities for police actions - they measure the outcomes of their work, not just the numbers of citations. Some departments use computer programs to better define the significant characteristics of high-crime locations. These correlates assist police and communities in creating place-based, as opposed to person-based, interventions.

Stop and frisk is one of many vital tools in a patrol officer's repertoire, but it is one that should be employed with a laser-like focus to respond quickly to an uptick in gun violence in a specified area, and it should also be used in conjunction with the practices proven to be effective in maintaining healthy communities.

Crime statistics in 2015 show the largest single-year increase in homicides since 1971. Guns were the weapon of choice in 87 percent of the additional murders. More than 50 percent of victims were black men. These are real lives lost. They matter.

Such violent victimization is a crime tax charged disproportionately to socio-economically disadvantaged Americans who are predominately black. And the violence police respond to in our cities is devastating.

Progressives should not allow Trump to co-opt stop and frisk. Instead, they should acknowledge it is a common component of discretionary police activity. Hillary Clinton should support policies that guide its more just application and trust that police will continue to employ it when necessary to prevent violent crime.

In the end, policing done well offers us all equal access to life, liberty, and the pursuit of happiness.

Michael J. Jenkins is an associate professor of criminal justice at the University of Scranton, a 2016-17 Fulbright scholar, and director of the university's Center for the Analysis and Prevention of Crime.