There is no legal requirement that lawsuits be settled by jury at all. The decision can rest in the hands of a judge alone. Having a jury, though is usually to the advantage of the defendant, because you have a statistically better chance of avoiding a conviction if a majority of 12 have to make the ruling as opposed to merely one, so you tend to see more jury trials in lawsuits than not.
Another alternative is called binding arbitration. To avoid the prolonged time frame and cost of a trial, both sides submit to the decision of a third party arbitrator, someone who weighs the evidence individually and his/her decision is final, as both sides must waive their right to appeal to use this option. Many times, a plaintiff will choose this option because by avoiding all of the appeals, they can be assured of getting some money much sooner.