PROVIDENCE, R.I. — At daily roll calls, where local cops have always assembled for amiable operational briefings, there are now uncomfortable questions.

The inquiries come, Providence police chief Hugh Clements said, from officers increasingly worried that doing their jobs may turn them into the next YouTube sensation, depicting yet another highly charged encounter between citizen and cop.

On the streets, where Maj. Tom Verdi spent the early days of his nearly three decades on the force, the respectful nods of acknowledgement have been replaced with some "hostile'' stares. And within the ethnically mixed South Side, Lt. Henry Remolina said the black and white uniform often renders him a stranger in the very neighborhood where he grew up.

There is no tying the tension here to any specific confrontation gone bad. No shooting, no beating captured on video. Rather, it is akin, law enforcement officials and community leaders said, to a powerful aftershock that has reignited long-unresolved social grievances in Providence and in many other cities across the country following the wave of civil unrest that swept through Ferguson, Albuquerque, Baltimore, Chicago, Cleveland, North Charleston, S.C., and Staten Island.

In the past 16 months, the so-called "Ferguson Effect" has become a staple in the American vernacular. Yet very few agree on what exactly that means and what it may portend for the future relationship between law enforcement and the communities they serve.