Briefly, motions for JMOL and summary judgment are very similar in that judges apply similar legal standards when deciding these motions, but they are different because they take place at different times during a civil case. Summary judgment is a pre-trial motion, JMOL is an in-trial or post trial motion.
In the federal courts JMOL is governed by Rule 50. The moving party must wait until its adversary has had an opportunity to present its case before moving for JMOL. In the motion, the moving party asks the court to rule in its favor because the law and the evidence demonstrate that the moving party must win on one or more issues. There is no need for a jury to deliberate. A motion for JMOL has tactical advantages because if the judge denies the motion, the moving party can move again after the trial (a “renewed” motion for JMOL) pursuant to Rule 59.
A summary judgment motion, Rule 56, also asks the judge to rule in favor of one party on one or more issues. Similar to JMOL, the motion argues that the evidence and the law so clearly favors the moving party that the judge should rule in the moving party’s favor. Typically motions for summary judgment take place after discovery is complete because at that point the parties have shared all the important evidence in the case. However, it is possible for a party to move for summary judgment earlier in the case, even before discovery is complete.
The diagram below might be helpful:
Summary Judgment motions usually follow discovery. JMOL is an in-trial or post-trial motion.