In a shaky moment, a smartphone camera captures a violent encounter between police and a member of the citizenry. But did the officer err — and what happens next?

Timothy Longo Sr., former chief of the Charlottesville Police Department, is teaching University of Virginia School of Law students what to expect during the investigation and litigation of police use-of-force cases as part of his new two-week short course, which begins today.

Longo says he wants to teach students, who may go on to work at a law firm representing either a plaintiff or a municipality and an involved officer, what unfolds "when a client walks in and says ' something went terribly wrong.'"

He said he will use two or three real cases that are not under protective order to illustrate points in his seminar-style class, called Understanding Police Use of Force: Investigation and Litigation Concepts.

"If you're that lawyer who gets this set of facts, what are you thinking about?" Longo said. "Most people who look at these cases, whether you’re a law student or just a regular person who has never been exposed to the law, say, 'My god, these cases are ugly.' But even the ugliest of cases are defensible."

Justice Department officials announced this month their latest findings of police excessive use of force — this time in a rebuke of the Chicago Police Department. But juries can be reluctant to punish officers when use-of-force cases arise. Police are authorized to use force, if they feel themselves or others are threatened, under the Fourth Amendment.

Longo retired as chief in May after 15 years in the role, with only a few officer-involved incidents during his tenure — and none that rose to the level of department-wide or national scrutiny. ("Call it a blessing, call it good fortune, call it what you will," he said.)

He previously served 19 years with the Baltimore Police Department, where he rose to the rank of colonel.

Currently, as assistant professor and program director for public safety administration, Longo is helping the UVA School of Continuing and Professional Studies build a new master's in public safety administration program, slated to launch in 2019. He also serves as a police practices expert who has appeared in court as a witness for both plaintiffs and defendants. In addition, he assists in the monitoring of two settlement agreements that resulted from Department of Justice pattern-and-practice investigations: United States of America v. City of Cleveland and United States of America v. Los Angeles County Sheriff’s Department.

Longo, who holds a J.D. from the University of Baltimore, prides himself on being able to look at law enforcement issues from all sides.

"I've had plaintiff's attorneys say, 'How do you feel about doing this? You've been a cop your whole life. And now you're sitting down before a jury on behalf a plaintiff who's suing the police. How can you do that?" he said. "Well, this is about justice. And who would you rather have explaining policing to a jury?"

Even though he feels he's objective, Longo said a benefit of the class is he can also humanize an officer's thought process, which often begins when dispatched. The assessment of threat, and how an officer might have to respond, is tempered by the many possible consequences if his or her actions are questioned, Longo said. They include possible criminal prosecution, civil lawsuits and administrative actions, up to loss of employment.

"But then there's this 'court of public opinion' that moves much quicker than the other three, often with far less facts," he said.

He noted that fatal shootings of police officers increased in the U.S. in 2016. He said that's no doubt adding to the anxiety many officers feel when responding to calls.

Founded in 1819, the University of Virginia School of Law is the second-oldest continuously operating law school in the nation. Consistently ranked among the top law schools, Virginia is a world-renowned training ground for distinguished lawyers and public servants, instilling in them a commitment to leadership, integrity and community service.