About 1 a.m. on Sept. 22, 1983, Lorin Johnson, 42, was standing at a bus stop at 12th and U streets NW when a car pulled up and the driver asked him if he wanted to buy some Preludin. The curly-haired, soft-spoken printer made a good deal -- one pill for $7 that he said he planned to use when he got home.

But, moments later, another car pulled up and the driver asked if Johnson had any Preludin to sell. Johnson sold him the pink appetite suppressant pill for $12.

The second motorist turned out to be an undercover cop and the $5 profit that Johnson made sent him to a federal prison for three to 10 years.

Johnson paid such a heavy price mainly because of his previous criminal record. He had been convicted of robbing a bank in 1973. Three years later, he was convicted of breaking into a Northern Virginia motel with three other armed men. In 1982, he was arrested for selling two Preludin pills to an undercover officer and was put on probation.

Johnson was a longtime addict who sometimes peddled drugs to get his fix. He went to trial to fight the drug charge because he was convinced that police had set him up.

"I'm a juggler, I'm not a dope dealer. There's a big difference," Johnson said during an interview at the Federal Correctional Institute in Ashland, Ky. "Your dope dealer is the guy who's putting it on the street. A juggler is just out there surviving, trying to get shot money.

"A guy will juggle until he gets enough money to get a shot. And when he does that, his pockets are empty again."

A Superior Court jury convicted him, which meant a mandatory minimum sentence of 20 months. At sentencing, defense attorney Marian Flynn asked Judge Ronald P. Wertheim for leniency.

"Your honor," she said, "it's obvious that this is the smallest possible cog of the wheel that's standing in front of you and this man is totally [insignificant]. There are hundreds like him out there."

Not entirely so, countered Assistant U.S. Attorney Jay Agee. "He may be a small drug dealer, but nevertheless, he's dangerous. He's a danger to the community, and we submit that he should not be allowed to get a free ride . . . . "

Wertheim went beyond the minimum provided by the mandatory sentencing law. He sent Johnson away for three to 10 years, telling him, "You might as well be selling death."

"I could never get across to him the point that it didn't matter where he got it from," the judge said recently. "You look at the guy's record and how long has he been doing this? . . . So clearly, this is a guy who's out there regularly peddling this stuff on the street. And Preludin is typically sold one pill at a time."

Johnson has appealed his conviction. After he did so, Wertheim last month agreed to shorten Johnson's sentence to 20 months to five years.