IN film and TV dramas, it all looks so easy. An outraged jurist - brimming with moral fervor - slams down a gavel and pronounces the defendant sentenced to ''10 years at hard labor!''
But sentencing, as anyone who does it for a living knows, is the hardest part of judging. To decide what punishment fits the crime - and the criminal - calls for a set of mental and moral balances that no human can possess or, many people think, should be allowed to use.
How reasonable it seems. The ''solutions'' fly thick and fast: Standardize the punishment process. Eliminate the wild disparities between the ''hanging judge'' and the ''bleeding heart.'' Bring sentencing out in the open. Make plain the price of evildoing. Tell every prospective malefactor: Committing the crime means doing the time.
Unfortunately, no two crimes and no two criminals are ever precisely equal. Consider Harry and Carey, brothers, who set out to wreak vengeance upon a bar bouncer. Harry knocked on the man's door, thus drawing him into the open, where Carey could pepper him (albeit not fatally) with a semiautomatic.
As joint participants in a single criminal enterprise, Harry and Carey were equally guilty. But should they draw identical sentences? On the one hand, only Carey had aimed and fired; on the other, Carey had never before faced serious criminal difficulty, while Harry had served frequent jail time.
If the law bound the judge to impose a specific, mandatory sentence, he could not differentiate between the brothers. Each would necessarily receive the same punishment.
Consider next teen-age Louis, who on thin, although sufficient, evidence had been convicted of his second attempt at purse-snatching, the first having occurred three months earlier. An in-depth presentence report by the Probation Department encouraged the judge to a reasoned conclusion that the two instances, coming so close together (and standing alone in an otherwise clear record), represented a singular adolescent outburst and that probation, not jail, was the most appropriate sentence.
In the world of mandatory sentencing, the judge would not have this option. Louis would receive the same punishment as a 40-year-old professional mugger.
Another fact of the human condition which statutory uniformization ignores is the dissimilarity between instances of the same offense. Start, for example, with the general belief that the law should condemn striking someone with a length of wood. Most people, however, would encourage the sentencing judge to distinguish between an assault that bruises an arm and one that fractures a skull.
Yet, in a penal code which ordains that anyone who commits an assault and battery with a dangerous object shall (not may) draw incarceration (not probation) for X years, the arm-bruiser and the skull-cracker will go to jail for equal periods.
Because that result is obviously unfair, the mandatory-sentence advocates have to build the necessary distinctions into the statute. Thus they enact statutory degrees of, for instance, assault, minutely defined. Even then, the legislation has to omit a gamut of reasonably likely situations.
Another way to accommodate the inevitable differences in proscribed conduct is to focus on the victim. Severity of punishment, that is, will relate directly to the extent of the physical damage caused. Here again, the infinite variety of possibilities paralyzes justice.
Finally, because the required incarceration depends so heavily on the precise nature of the crime charged, a large part of the sentencing function will revert to the policeman who decides what charge to press and the district attorney who decides what indictment to prosecute.
Are we better off having sentences imposed, as it were, privately? Or is justice healthier if the judges, with all their human imperfections, conduct the process in open court, on the record, where the prosecutor can recommend, the defendant can respond, the judge can try to fit the punishment to the circumstances, and - above all - the public can watch?