A CVS pharmacy is seen on fire after being looted, behind a line of police and a line of protesters (front) in Baltimore on April 27. (Michael Reynolds/European Pressphoto Agency)

A CITY that has lost a third of its population in a half-century; where police have earned notoriety for abusive, vicious and brutal community interactions; where homicide, drug crimes, teenage pregnancy, high school truancy, poverty and joblessness are endemic in some inner-city neighborhoods — it’s not hard to fathom how Baltimore has succumbed to rioting, or why other cities might do likewise. As President Obama aptly put it on Tuesday: “This is not new.

None of that excuses the knuckle-headed rioters who laid waste to neighborhoods where they live Monday, burning a drugstore where they might shop, a restaurant where they might eat and a senior complex where their grandparents might live.

The “idiotic” destruction — the characterization is Mayor Stephanie Rawlings-Blake’s (D) — was wanton, random and self-defeating. It said nothing, it solved nothing and it squandered the dignity and resolve of earlier protests calling out the police for the death of Freddie Gray, who died from a spinal cord injury a week after he was arrested by patrol officers on April 12.

Rioting is a senseless expression of anger and despair. It sheds no new light on problems that, in Baltimore’s case, are already well known.

Last fall, the Baltimore Sun published a shocking exposé of what it called “a frightful human toll” of police beatings and brutality, which had cost the city more than $11 million in settlements and legal fees in just four years, during which the city faced more than 300 lawsuits over police conduct. Dozens of cases from the same period were unresolved.

“Officers have battered dozens of residents who suffered broken bones — jaws, noses, arms, legs, ankles — head trauma, organ failure, and even death, coming during questionable arrests,” the Sun wrote in what was, given the horrific details unearthed in the reporting, an achievement of understatement. “Some residents were beaten while handcuffed; others were thrown to the pavement.”

The problems in the 2,800-officer police department, the nation’s eighth-largest, have deep roots and go back years. Mindful of what she has called the “broken relationship” between police and the communities they serve, Ms. Rawlings-Blake brought in an outsider as police commissioner, Anthony W. Batts, who had previously served as police chief in Oakland. His marching orders were to improve the department’s community relations.

That was just a start, and Mr. Gray’s death is grim evidence that much work is left to be done. That work needs to take into account not only the failings of the police but also of whole neighborhoods that have been left to wither in despair. Fundamentally, what is lacking in Baltimore is a sense that justice — social, economic and otherwise — is accessible to residents regardless of their circumstances.

Rioting is not an effective means of advancing justice or any other desirable outcome. As Mr. Gray’s mother, Gloria Darden, said as the city burned on Monday: “I want you all to get justice for my son, but don’t do it like this here. Don’t tear up the whole city. . . . It’s wrong.”