A demurrer to evidence is a motion made during trial that asks the judge to end the case because the other side’s proof, even taken at face value, is legally too weak to support a verdict. The moving party argues that no reasonable jury could rule for the opponent on what has been presented. A handful of states still use the term, but most modern courts call the same motion a “motion for judgment as a matter of law” in civil trials and a “motion for judgment of acquittal” in criminal ones. The mechanics are essentially the same whichever label the court uses.
Not the Same as a Demurrer to Pleadings
The two motions sound alike and target completely different things. A demurrer to pleadings challenges the legal sufficiency of a complaint before trial: it asks whether the written allegations, even if true, state a valid claim. A demurrer to evidence happens mid-trial and challenges whether the proof actually presented in court supports the claim.
California, for example, still uses the word “demurrer” in its rules, but only for challenges to pleadings. Oklahoma still uses “demurrer to evidence” for the mid-trial version, and under its statute a party may “interpose and file a demurrer” after the opponent finishes presenting evidence, “upon the ground that no cause of action or defense is proved.”1Justia Law. Oklahoma Statutes Title 12 – Section 12-577 In federal court, neither term appears in the current rules. Older case law using the phrase “demurrer to evidence” describes what federal courts now handle under Rule 50 of the Federal Rules of Civil Procedure or Rule 29 of the Federal Rules of Criminal Procedure.
When the Motion Is Filed
The natural moment is right after the party carrying the burden of proof rests, and before the defense presents its own case. In federal civil practice, Rule 50 allows the motion once the opposing side has been “fully heard on an issue,” and it can be made “at any time before the case is submitted to the jury.”2Legal Information Institute. Federal Rules of Civil Procedure Rule 50
In federal criminal cases, Rule 29 explicitly allows the motion both “after the government closes its evidence” and “after the close of all the evidence.”3Legal Information Institute. Rule 29. Motion for a Judgment of Acquittal Filing at the close of the prosecution’s case is the more common move, since it offers a chance to end the trial before the defendant has to put on any evidence.
The motion is typically made orally in open court, though judges sometimes ask for written briefing when the issues are complex. Local rules and standing orders vary, so it is worth checking the specific court’s requirements before trial.
What the Court Looks At
The judge does not weigh credibility or decide who to believe. The court views the evidence in the light most favorable to the party opposing the motion and asks one question: could a reasonable jury find for that party based on what has been presented? If the answer is no, the motion should be granted.2Legal Information Institute. Federal Rules of Civil Procedure Rule 50 The federal criminal standard is the mirror image: whether “the evidence is insufficient to sustain a conviction.”3Legal Information Institute. Rule 29. Motion for a Judgment of Acquittal
The bar is not high. Courts are not looking for overwhelming evidence but for legally sufficient evidence. Most federal and state courts apply a “substantial evidence” standard, which requires more than bare suspicion or conjecture. Inferences are allowed if they flow from logic and the actual proof rather than speculation. In practice, the motion succeeds most often when the opposing party has a gap in its case: a missing element of the claim that no reasonable jury could fill in. A weak case that still covers every required element usually survives. An argument that the evidence is merely “not persuasive” almost never wins, because credibility is the jury’s job.
What Happens If the Court Grants the Motion
Civil Cases
The court enters judgment against the party whose evidence fell short. Whether the case can be brought again turns on whether the dismissal is “with prejudice” or “without prejudice.” A dismissal with prejudice means the plaintiff cannot bring the same claim again.4Legal Information Institute. With Prejudice A dismissal without prejudice technically leaves the door open, though refiling is difficult when the evidence has already been aired and found wanting.
The losing party can appeal. Appellate courts review these rulings de novo, meaning they look at the evidence independently rather than deferring to the trial judge’s read.
Criminal Cases
The consequences are larger. Once a trial judge acquits a defendant, “there is no possibility of retrial for the same offense” under the Fifth Amendment’s double jeopardy protection.5Congress.gov. Amdt5.3.6.3 Acquittal by Trial Judge and Re-Prosecution The Supreme Court has held that even an acquittal resting on “an egregiously erroneous foundation” is final and unreviewable.
There is one narrow exception. If the jury convicts and the judge then enters a judgment of acquittal, the prosecution can appeal, because a reversal would simply reinstate the jury’s guilty verdict rather than force a new trial.5Congress.gov. Amdt5.3.6.3 Acquittal by Trial Judge and Re-Prosecution Timing therefore matters: an acquittal entered before the jury deliberates is far harder for the government to challenge.
What Happens If the Court Denies the Motion
The trial continues, and in federal court denial carries no penalty. The defense presents its evidence, and the case proceeds to the jury as if the motion had never been made. Under Rule 50, the court treats the denial as having “submitted the action to the jury subject to the court’s later deciding the legal questions raised by the motion.”2Legal Information Institute. Federal Rules of Civil Procedure Rule 50 Rule 29 expressly protects a criminal defendant’s right to present evidence after the motion is denied, “without having reserved the right to do so.”3Legal Information Institute. Rule 29. Motion for a Judgment of Acquittal
This is a significant departure from the old common law. Historically, a defendant who demurred to the evidence effectively admitted the facts and gave up the right to put on a defense. If the demurrer was overruled, judgment followed without any chance to call witnesses. Modern rules eliminated that trap, and the Rule 50 Advisory Committee notes state that “the formality of an express reservation of rights against waiver is no longer necessary.”2Legal Information Institute. Federal Rules of Civil Procedure Rule 50 Oklahoma’s statutory version likewise does not force the moving party to forfeit the right to present a defense if the demurrer fails.1Justia Law. Oklahoma Statutes Title 12 – Section 12-577
Renewing the Motion After Verdict
Losing the initial motion is not the end of the road. In federal civil cases, Rule 50(b) allows a party to file a renewed motion for judgment as a matter of law no later than 28 days after entry of judgment. If the motion concerns a jury issue not decided by a verdict, the deadline runs 28 days from when the jury was discharged.2Legal Information Institute. Federal Rules of Civil Procedure Rule 50 The renewed motion can also include a request for a new trial under Rule 59.
In criminal cases, Rule 29(c) gives the defendant 14 days after a guilty verdict, or after the jury is discharged, whichever is later, to move for a judgment of acquittal or renew a previously denied motion. The defendant does not need to have moved for acquittal before the jury deliberated in order to make the motion afterward.3Legal Information Institute. Rule 29. Motion for a Judgment of Acquittal If the court grants the post-verdict motion, it sets aside the guilty verdict and enters an acquittal.
These deadlines are more than housekeeping. In many circuits, failing to make a Rule 50(a) motion during trial means you cannot raise the sufficiency of the evidence on appeal at all. The initial motion preserves the issue; the renewed motion forces the trial court to rule definitively.
Why Lawyers File It Anyway
Because modern versions of the motion carry no waiver risk, there is almost no downside to making it. Defense attorneys routinely move for judgment as a matter of law at the close of the plaintiff’s or prosecution’s case even when the odds of success are low, simply to preserve the issue for appeal. The real risk is skipping the motion.
When the opposing side has left a clean hole, the motion is genuinely powerful. The plaintiff proved damages but offered no evidence of causation. The prosecution established that a crime occurred but never connected the defendant to it. Judges grant these motions when the gap is obvious.
In criminal cases the risk-reward is lopsided. If granted, double jeopardy typically bars retrial and the defense wins permanently. If denied, the defendant simply continues with the trial. That asymmetry is why experienced criminal defense attorneys almost always make the motion.