If you're white, and you're a civil rights worker, it's a good bet that meeting Charles Sims would be unpleasant. His grizzled face and scruffy clothes look engaging only from a distance; once you come close to the man, he stares you down, and you want to disappear. There is something hostile, even belligerant in his eyes. Without opening his mouth, he seems to be saying, "I don't like you."

But this much has been written elsewhere. Charles Sims is already famous in the South, the black man who won't turn the other cheek. He preaches, instead, the art of self-defense.

Sims is the spokesman for the Deacons for Defense and Justice, an armed Negro police organization that is spreading across the rural South and into Northern cities. He reigns over the most famous of the Deacon chapters, in Bogalusa, La., and his exploits there prompted Jet magazine to label him "The man most feared by whites in Louisiana."

Charles Sims, the man, lives up to his press clippings. He is underworldly, too brazenly intimidating to be called sinister. He has beady eyes. He sneers humorlessly, through a gap in his gums where two teeth used to be. He is paunchy, but the excess bulk only adds to the overall projection of power. Somehow, one feels, that must be muscle bulging over his belt.

And when Sims finally speaks, it is hardly a reprieve. He is contemptuous of reporters and of the general public; he has toyed with both since he arrived here two days ago on a fund-raising tour. At his press conference Wednesday, a newsman asked, "Have you ever been arrested?"

"I've been in jail 27 times," Sims answered indifferently. "Three cases of speeding, about twenty cases of battery..."

"Battery with what?" the newsman interrupted, and Sims clenched his fist and held it forward.

In Bogalusa, the other Deacons take their cue from Sims. They are just as mysterious, just as hostile, and even less accessible. While in Bogalusa this summer, I asked Sims the size of his organization, and he growled, "I don't want nobody to know how big or how small we are. It's the idea alone that cuts down a lot of the crap." I put the same question to a few of his lieutenants and got no answer at all.

If all this makes the Deacons sound like a gang of mute hoodlums, and Charles Sims like the czar of the underworld, it shouldn't. Bogalusa is a strange town, a mean town; the niceties of non-violence seem inappropriate in a place where half the cars fly rebel flags and the radio station announces Klan rallies as though they were church picnics.

Bogalusa ignores the Civil Rights Act of 1964. Until a year ago, the mail wasn't even delivered to Negro homes. White moderates -- there are a few -- apologize in whispers for their neighbors: "These people don't know any better; they're ethnic Mississippians."

During the summer, when there were demonstrations almost every day, the mayor and the police chief admitted they were powerless to protect Negro lives and property. They called on Louisiana Governor John McKeithen, who sent in 600 state troopers, armed them with submachine guns, and told them to protect the marchers. Still there were incidents.

Bogalusa provides a rationale for a Negro self-defense organization, and from what I saw during the week I was there, that's all the Deacons are.

The Bogalusa Deacons are never heard and seldom seen. They guard the homes of civil rights leaders at night. They provide armed escorts for rights workers traveling into, out of, or across town. During every march, six or seven of them sit quietly in cars, parked at strategic points along the parade route. They don't make daring sorties into the white neighborhoods or exact any sort of revenge. They seem much more like a volunteer suburban security patrol than dashing vigilantes.

No member, according to Sims, has ever been charged with a felony; this record is a credit to the discipline of the organization, and the discipline of the organization is a credit to Sims. He discourages in private the bellicose attitude that he projects in public. His Deacons are merely a deterrent force to scare off racists who are hunting for trouble. Sim's aim is simply to keep the Klan out of Negro neighborhoods, and in this he succeeds. He has created a Cold War atmosphere in Bogalusa. No gunfights, no midnight raids, only sitting and waiting.

Why then the snarling exterior? For one thing, it's good tactics. In the protection business, the grizzly rumor serves better than modest fact. If the white Southerner thinks the Deacons are more like the Gestapo than Pinkerton's Security Service, why enlighten him?

And if it weren't for the snarl, Sims and the Deacons would not be famous today. It's the gangland reputation, the toothless sneer, that have won the man and his organization front-page coverage in newspapers across the country. As long as Sims maintains the mystique, the American press will do his proselytizing and fund-raising for him. Sims estimates that there are now 50 to 60 Deacon chapters in existence, and it's a cinch that most of these were inspired by newspaper accounts alone. Sims told me, "I don't really like publicity. I'd never talk to the press if their noise didn't help me."

It would be wrong to say that the snarl is only a pose. Sims actually is a little bit sour on the world. "We might not have organized the Deacons if Katzenbach had sent troops to Bogalusa when they were needed," Sims told Wednesday's press audience. "There's gotta be law."

"I'd like to take a rest, but the police won't let me," he said in one of his meeker moments, "I'm just doing the job no one else will do."