The videotaped images of Los Angeles policemen taking turns clubbing and kicking a lone suspect with apparent abandon suggest for Dr. James McGee the animal instincts that surface when humans acting in groups get swept into a frenzy.
"Human beings are far less removed from our animal ancestors than we'd like to think," said Dr. McGee, director of psychology at the Sheppard and Enoch Pratt Hospital and a therapist for the Baltimore County Police Department.
"Humans are pack animals. Just looking at the tape could remind you of a pack of animals attacking a prey. You see a pack of lions bringing down the wildebeest, how they're all getting their licks in."
Psychologists who serve America's police departments seem to agree that the potential for senseless brutality exists within practically any police agency where officers face violence, drugs, high-powered weaponry and public disrespect for the jobs they perform.
It's up to the departments, they say, to screen out applicants who are psychologically ill-equipped for police work and to create an ethic that brutality is unacceptable. It's also imperative, they say, for departments to offer counseling to police officers who are boiling over with stress and to make it "OK" for officers to seek such assistance.
Some departments do these things, but many do not -- and psychologists seem to agree that the Los Angeles incident bears the earmarks of a department where intolerance is made morally acceptable from the top down and where officers who mete out curb-side justice are rewarded rather than disciplined.
"The capsule analysis is that this is a situation that got out of hand, and the very public nature of it implies that it is not an isolated incident," said Dr. Charles Bahn, a forensic psychologist at the John Jay College of Criminal Justice in New York who advises that city's police department.
"Police get a double message: a rhetorical message that it's not acceptable and a policies-and-practice message that it's not only acceptable but it earns you respect."
Dr. Bahn insists that "you don't need a national inquiry" to find police forces where brutality is acceptable and even commonplace. "All we have to do is look a little and we will find it in other American cities. You can determine what departments it takes place in -- those where brutality complaints are dismissed out of hand and where there's no counseling for the officers involved."
Far from branding police officers as bad people, the psychologists say law enforcement poses a pressure cooker of demands that can motivate good people to act with cruelty.
Dr. Harvey Schlossberg, a former New York City police officer who left the force to become a psychologist, said the people attracted to police work tend to be conservatives: believers in law and order, defenders of the status quo, opponents of non-conformity. On the job, they confront city streets that verge on anarchy.
"The amount of violence against police has increased with the kinds of weapons out there," said Dr. Schlossberg.
In response, he said, police officers come to see themselves as a minority group: "It becomes them and us. We're united against them. . . . One builds up a vigilante justice, a sense that the only way we can see justice is to strike out, to become judge and jury."
Dr. Schlossberg said the problem is compounded by the popular culture that glamorizes Clint Eastwood and Sylvester Stallone renegades for their cold determination to mete out justice no matter what. "It becomes very Machiavellian. The ends justify the means. That's what they're brought up on."
But he added, "Brutality is not indiscriminate. There's always an incident that triggers the brutality. What happens is that the party involved -- in this case, the policeman -- loses the perception of reality. They get caught up in the fantasy. As the momentum builds, the boundaries of fantasy and reality begin to fade."
When police officers respond en masse to a crime scene, said Dr. Bahn, their highest priority is to protect each other. A tricky group dynamic can take over.
Responsible behavior can prevail if everyone acts responsibly. "But if one person starts acting brutally, the balance moves toward manhandling or tough handling," Dr. Bahn said. "Even those who detest violence -- and there are officers who do -- will for reasons of group dynamics behave more violently than they otherwise would."
He said many police officers also feel that society has grown so cynical about the justice system and the get-tough promises of politicians that it has given them a mandate to punish criminals where they find them.
They may also get a mandate from their superiors: "In non-verbal ways, police officers who are known as physically tough are often allocated special honors and promotion opportunities within the department," Dr. Bahn said. "Without saying so, many chiefs imply that the officer is looked upon as heroic within his own department."