Every year, dozens of convicted supplicants come before a stern triumvirate of Montgomery County Circuit Court judges to beg for a lighter sentence.

Virtually all the pleaders go away, if not with a reduction in their jail terms, then at least none the worse for trying.

Now comes Donald L. Hawke.

The insurance agent, who was sentenced to a one-year jail term for misappropriating at least $15,000 from the city of Rockville, recently threw himself on the mercy of the court.

The three-man panel agreed that Hawke's sentence was wrong. But instead of reducing the term, the judges upped it to 18 months in jail.

As Judge John J. Mitchell put it, Hawke "rolled his dice and came up boxcars."

Because penalties can be raised as well as lowered, requests for sentence review are gambles, but as gambles go, the odds favor the petitioner.

In Maryland's eight circuit courts in 1978, 273 people asked for lighter sentences. Thirteen petitioners received them, and though everyone else was turned down, no sentences were increased.

Last year, 251 people came hat in hand before sentence review panels in the state and only 20 were granted sentence reductions.

Hawke, the city's insurange agent and former president of the Rockville Rotary Club, was convicted last year of misappropriating Rockville insurance funds. Prosecutors said that between 1975 and 1978, Hawke billed the city for lump-sum premium payments as large as $300,000, but paid the insurance company in quarterly installments.

"He always paid the premium," said prosecutor Matthew Campbell, "but in the meantime he made money on the interest to the lump sum, and he hid the fact from the city and the insurance company."

Sentenced to a one-year jail term in September by Judge Philip M. Fairbanks, regarded as one of the more strict circuit court judges, Hawke had the misfortune to encounter a review panel that was beginning to crack down on persons convicted of white collar crimes.

"People are becoming increasingly concerned with the light-handed manner in which white collar criminals are dealt with," said Judge Mitchell, who concurred with Judges Joseph M. Mathias and Stanley B. Frosh that "crimes of greed" merited punishment as much as "crimes of need."

"White collar criminals are bleeding us just as much as other criminals," said prosecutor Campbell. "But a robber has three to four times a better chance to go to jail."

Hawke, who is free pending appeal, had asked for a reduced sentence on the grounds that he had made restitution, had dependent children and had been given an unduly harsh sentence that had devastated his business.

Although he is appealing his conviction, Hawke will not get another chance to have his sentence -- now 18 months -- reviewed.

In an interview, he explained his reaction.

"If you are a salesman, you try to get out (and sell) in this environment," the stunned Hawke said. "I was wrong and I'm going to pay my penance. But it's going to take a lot of drive, a lot of gumption and a lot of love. It's going to take every morsel to keep going."