For a judge, the primary incentive for accepting a plea bargain is to move along a crowded calendar. Most judges simply don't have time to try every case that comes through the door.

Additionally, because jails are overcrowded, judges may face the prospect of having to release convicted people (housed in the same facilities as those awaiting trial) before they complete their sentences. Judges often reason that using plea bargains to "process out" offenders who are not likely to do much jail time leads to fewer problems with overcrowding.

For a prosecutor, the judge's concerns about a clogged calendar are the prosecutor's concerns as well. When the judge is bogged down, the judge puts pressure on the prosecutors to move cases along quicker. To keep judges happy -- and keep the machine rolling -- prosecutors must keep "the bodies" moving (as criminal defendants are most unfortunately referred to by some courthouse regulars).

Of course, prosecutors are also concerned about their own calendars. Crowded calendars mean that the prosecutor's staff is overworked. Plea bargains tend to lighten everyone's caseload. Because plea bargains are much quicker and require less work than trials, they are also easier on the prosecutor's budget. With today's cutbacks on already slim resources, prosecutors feel they will have additional time and resources for more important cases if they conclude a large number of less serious cases with plea bargains.

Another benefit to the prosecution is an assured conviction. No matter how strong the evidence, no case is ever a "slam dunk." The prosecution may wage a long, expensive and valiant battle, and still lose the case -- as did prosecutors in the O.J. Simpson criminal trial, for example.

Plea bargains also give prosecutors flexibility. For instance, they can offer a deal to someone whom, though guilty, has given testimony about a co-defendant or helped resolve some other troubling case.

Finally, prosecutors may use plea bargains to circumvent laws they don't agree with. For instance, a prosecutor may disagree with laws prohibiting possession for personal use of small amounts of marijuana, so the prosecutor's office may have an unwritten policy of giving all such offenders "offers they can't refuse," such as a $25 fine and 10 hours of community service. Or, in some cases, the prosecutor may simply dismiss the case in the interests of justice.