A motion for summary judgment is a request by one party to a judge in a civil case that the judge make a decision on some or all aspects of the case before it goes to trial. A summary judgment motion must hinge on questions of law, not on questions of fact. The person who requests the motion for summary judgment is called the moving party, and he makes the request if he believes that there is no dispute about the facts in the case and if he believes the law dictates a simple answer.
In the United States court system and many other jurisdictions throughout the world, a person who is sued is entitled to a trial by a jury of his peers. This means that a judge typically will not make certain rulings or decisions about guilt or innocence, unless the parties waive their right to a jury trial. The jury makes the decisions after the trial process is complete, based on its understanding of the evidence, the facts and the application of the law.
Before a case gets to a jury, however, one of the parties can make a motion for summary judgment as part of the pretrial procedures. This motion asks the judge to decide the resolution of all or part of a case on the basis of the information and evidence presented thus far in legal briefs, motions and pleadings. In other words, the party who is moving for summary judgment essentially says to the judge that there can be no other possible way to interpret the law and so there is no point in going to trial.
Parties move for summary judgment in order to avoid discovery — in which they turn over documents — and to avoid the risk of a trial. The motion is only properly granted if there are no possible issues of fact. Ultimately, this is because the distinction between what juries and judges can decide comes down to a question of fact versus a question of law.
Only a jury can decide how the facts should apply in a given case and whether to believe one side or the other. For example, if the plaintiff claims the defendant was speeding but the defendant claims he wasn't, the jury has to decide who to believe. If both parties agree that the defendant was speeding, on the other hand, all the judge would have to do is apply a law about speeding. Thus, a motion for summary judgment would be appropriate since the judge could answer the question of whether the speeding law applies.
The party who opposes the motion for summary judgment need only show that there is a question of fact. If he does so, the case will proceed to trial on that particular issue. He needn't prove the full case to the judge, he only has to show that questions exist that the jury must answer.