For sheer outrage and stupidity, I thought nothing could top the story of Robert Bates, Jr., a federal attorney who was arrested in Chicago a few weeks ago for saying the words "damn" and "bastard" in public.

I was wrong. Bob Koester, 48 , a record store owner, was not only arrested for swearing in Chicago, he recently was convicted.

Like Bates, Koester was seized for swearing at a CTA employee. These employees, who not too long ago were stamping around with picket signs threatening to bring Chicago to its knees are apparently the most thin-skinned and sworn-at people in the world.

A few weeks ago, Koester was trying to get on a southbound L at Berlmont. It was a Saturday and things weren't very crowded, but the driver closed the doors on a bunch of passengers while they were trying to get on board. Then the train sped off.

A door closed on Koester's finger -- the door had rubber panels so it didn't hurt him -- but he was foot-stomping mad.

And he got madder and madder waiting for the next train. By the time the next train actually did come along, he already was composing nasty letters to the Chicago Transportation Authority in his head.

Then he took a deep breath and thought: Maybe some emergency had caused the earlier train to rush away. Maybe there was a good reason.

So, after he got on board the next train, Koester went up to the conductor and asked if there was some kind of emergency.

"Not as far as I know, " the conductor said.

"Oh, yeah?" Koester said getting angry again. "Well that motherblanker in the last train left a bunch of us stranded!"

I have changed Koester's actual swearword, but you get the idea.

You're a real potty-mouth, I told Koester.

"Aw, come on, this guy was a streetcar conductor!" Koester said. "He'd heard it before."

The driver did not care if he had heard it before. He pretended enormous shock. Keep in mind that Koester wasn't even calling him a bad name. He was calling the other conductor a bad name.

Koester went back to his seat feeling a little better. He noticed that the train halted in the darkness before pullling into the Grand Avenue station, but didn't know why until they arrived.

It was then he saw the cops. There were four of them and they had come in two squad cars and a patrol wagon. Koester figured there must be a pretty big criminal on the train to bring out all these cops. And as he got off, he started looking around for him.

That's when a cop came up to him and slapped a handcuff on his wrist. Koester was being arrested for swearing. He was being arrested for violation of Municipal Code of Chicago Section 192-7, which makes it a crime to swear within the city limits.

Koester thought the cops were kidding.

"You're kidding," he told the cops.

"Not us," the cops said. They took him down to the East Chicago police station, where he posted a $35 bond.

Then came the clincher to a perfect day. When Koester got back on the L, somebody picked his pocket. He got butted by a guy in front of him and then felt a hand go into his back poclet. He turned around in time to grab his wallet out of the second guy's hand.

Koester started yelling "Pickpockets! Pickpockets on the train!" The doors opened for the next stop and the two guys ran off.

Koester ran to the conductor. "Call the police!" he shouted. "Pickpockets!"

The conductor stared at him. "I don't see no pickpockets," the conductor said. Then he turned away. Koester went home shaking his head. He had learned a lesson. "It's okay to steal on the CTA, but you have to watch your language," he said.

You don't need me, the lawyer said. Go to court and the judge will throw the whole thing out. Don't be silly. Nobody gets convicted for swearing.

So Koester went to court. The conductor was there with a lawyer representing him. The conductor repeated Koester's swear word to the judge. The judge turned to Koester for an explanation.

"Well, judge," Koester said. "I mean, let's be realistic. This guy has heard the word before. It was not like his first time."

"It is a disgusting word," the judge said.

"Yeah, okay, I know, "Koester said. But I mean, you know, I'm in the music business and the word is heard a lot among musicians and this is 1980 and . . ."

"Guilty," the judge said. "Thirty days' supervision. Next case."

That sentence means if Koester swears in public in the next 30 days, he will be punished to the full extent of the law.

I asked Koester if he was watching his mouth.

"Around streetcar conductors I am," he said.