Defenses and the Burdens

Defenses and the Burdens

The earlier sections fixed what the prosecution must prove: every element of the offense, beyond a reasonable doubt. Many trials turn on something the elements never mention. A defendant who admits the act may say it was justified by self-defense, excused by duress, or the product of insanity, and the question becomes who must prove what about that claim. The answer has two layers, and the Model Penal Code (the Code) states them in its general rule on proof. That rule requires each element to be proved beyond a reasonable doubt, but it does not require the prosecution to disprove an affirmative defense unless and until there is evidence supporting that defense, and it does not reach a defense that the Code plainly requires the defendant to prove.¹

The first layer is a threshold, and its reason lies in who holds the facts. The evidence behind a justification or excuse usually sits with the defendant: what the complainant did, what the defendant believed, what pressure was applied. The prosecution cannot know which of many conceivable defenses a defendant will raise. A rule obliging it to refute all of them in every trial, with no factual basis in the record, would fill each case with proof about events nobody claims occurred. So the defendant carries the burden of production, the duty to come forward with enough evidence to put the defense in play. Once that duty is met, the defense bears on guilt, and the prosecution must disprove it beyond a reasonable doubt. Without that second step, the production requirement would quietly become a persuasion burden, because a jury that was merely unsure whether the defense applied would be left with nothing but the defendant's failure to prove it.

The second layer is narrower. For a true affirmative defense, the legislature may go further and assign the burden of persuasion to the defendant, so that a jury left evenly balanced must reject the defense. The Code permits this only where it plainly says so.² The Constitution leaves the legislature considerable room. Under Patterson v. New York and the decisions that followed, whether such an assignment is valid depends primarily on whether the legislature labeled the fact an element or a defense.³ On that footing the Court has upheld placing the burden on the defendant for insanity in Leland v. Oregon, for duress in Dixon v. United States, and for self-defense in Martin v. Ohio.⁴ The room has an edge. A defense that simply negates an element, with alibi as the standard example, is one the Constitution presumably does not allow the legislature to assign to the defendant, because disproving an alibi is only another way of proving that the defendant committed the offense.⁵ Mullaney and Patterson drew that boundary from the constitutional side, and the Code's own category of affirmative defenses draws a related one from the statutory side, which a later section examines. The next two subsections take the layers in turn, production first and then persuasion.

Step three is where the Code's definition of an affirmative defense does its work, since the Code's disproof rule turns on that status. Candidates lose points in two directions: some assume that any defense can be assigned to the defendant, and others assume that the prosecution must disprove every defense before the defendant has offered a scrap of evidence for it.

Burden of Production on Defenses

Self-defense and entrapment show the production burden at its simplest. Neither is ordinarily listed among the elements of the offense, so the prosecution's case does not have to address it. Each nonetheless claims that conduct the prosecution has proved should not result in conviction. With the exception of insanity and the rare statutes creating a true affirmative defense, the only burden the accused carries on such a defense is to produce enough evidence to inject it into the case.⁷ The burden works as a gate. A defendant who clears it has made the defense a live issue, and a defendant who does not has left the defense out of the trial, so the jury never considers it as a ground for acquittal. The consequence differs from the one the prosecution faces on its own production burden, because a failure of evidence on an element requires the court to enter a judgment of acquittal.⁸

How much evidence is enough is described in several ways. Courts speak of evidence that fairly raises the issue, of slight evidence, of some credible evidence, or of some evidence amounting to more than a mere scintilla, meaning more than a trace.⁹ The Code takes the position that evidence sufficient to raise a reasonable doubt is the proper measure.¹⁰ No verbal formula can describe the quantity or quality of evidence with precision, so the differences among these formulations rarely change the outcome. What they share is a low bar, and the bar is low because the persuasion burden still sits with the prosecution. The quantum of evidence generally tracks that allocation. Where the prosecution must disprove the defense beyond a reasonable doubt, evidence that would raise a reasonable doubt gets the issue to the jury. A defendant who must also persuade by a preponderance has to produce evidence from which a reasonable jury could find the defense more likely than not. The threshold still screens out a defense resting on nothing but counsel's say-so, since the facts behind a justification usually sit with the defendant, and a defendant who can point to none of them has shown no basis for asking jurors to consider it.

Two features of the production burden are easy to overlook. The first is where the evidence may come from: the burden is met when sufficient evidence has been introduced by any party, so the defendant need not testify or call a witness if the prosecution's own witnesses supply the facts.¹¹ Once the issue is injected into the case, the government must prove the contrary beyond a reasonable doubt.¹² The second is who decides. Whether the burden of producing evidence has been satisfied is a question for the court in administering the trial under Federal Rule of Evidence 104(a), and it is not a proper subject of instruction to the jury.¹³ The reason lies in what the question asks. It asks whether the record holds enough to let a reasonable juror consider the defense, which is a threshold judges apply to every issue in every trial. The jurors' task starts only after the threshold is crossed, when they are told that the prosecution must disprove the defense beyond a reasonable doubt. A production instruction would invite jurors to second-guess a gatekeeping ruling and would blur the one burden they actually apply.

Entrapment follows the same pattern. A defendant who claims that government agents induced the offense must put evidence of that claim into the record before the prosecution is required to answer it, and once the evidence is there the government bears the burden of disproof.¹⁴

The constitutional decisions on burden shifting leave this rule undisturbed. Patterson v. New York and Martin v. Ohio deal only with the allocation of the burden of persuasion, and the courts have had no trouble with an affirmative defense that simply requires the defendant to bear a burden of production.¹⁵ Even where a state makes the absence of self-defense an element of the crime, which forbids placing the persuasion burden on the accused, the accused may still be required to introduce at least some evidence of self-defense before the issue goes to the jury.¹⁶ The two production burdens appear side by side in Patterson itself. The State had to produce evidence that Patterson caused the death and did so intentionally, while Patterson, who had confessed before trial, carried the burden of producing evidence of extreme emotional disturbance.¹⁷ The Code states the same threshold in its own terms, for its rule that each element must be proved beyond a reasonable doubt does not require the disproof of an affirmative defense unless and until there is evidence supporting that defense.¹⁸ The words unless and until fix the timing. Before any evidence exists, the prosecution has nothing to disprove, and the moment evidence from any source supports the defense, the duty to disprove arrives.

On an exam, the first question about a defense is whether the stem contains evidence of it, and the strength of the defense comes second. Students lose this issue when they treat counsel's assertion as evidence that raises the defense, and they err in the other direction by requiring the defendant to persuade the jury when the stem asks only about getting the issue submitted. Check who supplied the facts, because testimony elicited from the prosecution's own witness counts, and remember that the judge, not the jury, decides whether the threshold has been met.

Burden of Persuasion on Defenses

The production burden gets a defense into the trial. The persuasion burden decides who loses when the jury cannot make up its mind about the defense once it is there. A legislature may sometimes assign that second burden to the defendant. The assignment is consistent with In re Winship, which held that the Due Process Clause protects the accused against conviction except on proof beyond a reasonable doubt of every fact necessary to constitute the crime charged.²⁰ The reason lies in what the prosecution has already done by the time a defense is reached. Once the jury has found every defined element, including the required mental state, beyond a reasonable doubt, the defendant stands proved to have committed the offense as the legislature described it. A true affirmative defense then asks the jury to excuse or justify conduct that is already proved, so requiring the defendant to carry that request leaves the proof of the crime undiluted. Justice Rehnquist made the point for insanity in his concurrence in Mullaney v. Wilbur: after a state has proved the killing and the required mental state, it may reasonably ask a defendant who wants to escape punishment entirely to bear the heavy end of the proof on that issue.²¹

The allocation matters most when the jury is evenly balanced. If the defendant carries the burden by a preponderance, a jury that finds the defense no more likely than not must reject it. If the prosecution carried the burden of disproof, that same jury would harbor a reasonable doubt about whether the defense failed and would have to acquit. The persuasion burden therefore settles every tie, which means it can decide a trial without changing a single fact. It also tracks who holds the evidence. The defendant is the party asserting the unusual event, such as a threat, an illness, or an attack, and the facts behind it lie largely with the defendant, so ordinary practice puts the risk of failed proof on that party.²²

The Court has applied this reasoning to three classic defenses. In Dixon v. United States the accused claimed duress in a federal prosecution and argued that once she raised the defense, the government had to disprove it beyond a reasonable doubt. The Court disagreed and held that, consistent with the common-law view, the defendant could constitutionally be required to carry the burden of persuasion on duress.²³ That common-law pedigree is real, since many states historically put both the production and persuasion burdens on the accused for classical affirmative defenses such as insanity and self-defense.²⁴ Leland v. Oregon upheld placing the insanity burden on the defendant, and Martin v. Ohio did the same for self-defense.²⁵ What links the cases is sequence. In Leland the insanity issue reached the jury only after it had found every element, mens rea included, proved beyond a reasonable doubt, and legal insanity bears no necessary relationship to whether the required mental element was present.²⁶ Martin adds a condition about instructions. Ohio defined murder as purposely causing death with prior calculation and design, and the conviction stood because the jury was told that the State carried every element, prior calculation and design included, and that it could weigh the self-defense evidence in deciding whether any element had been proved beyond a reasonable doubt.²⁷ That instruction keeps the defendant's persuasion burden on the defense and off the elements.

How heavy the defendant's burden is depends on the system. Under federal law, a defendant who must establish a true affirmative defense, which few federal statutes create, carries it by showing the defense more probably true than not, a preponderance, while insanity requires the higher measure of clear and convincing evidence.²⁸ The Model Penal Code allocates persuasion more sparingly. Its rule that the prosecution must prove each element beyond a reasonable doubt does not apply to a defense that the Code or another statute plainly requires the defendant to prove by a preponderance of the evidence.²⁹ The word plainly places the drafting burden on the legislature, so a defense the statute does not clearly assign to the defendant remains one the prosecution must disprove once it is raised.

The same reasoning that permits the allocation also marks its limit. A defendant can be made to carry a defense only when the defense adds a separate ground for excuse after the elements are proved. If the so-called defense merely negates an element, putting persuasion on the defendant would let a conviction rest on less than proof beyond a reasonable doubt of that element, because a jury unsure whether the element existed would be told to convict unless the defendant dispelled the doubt. Mullaney v. Wilbur applied that logic. Maine required the defendant to prove by a preponderance that he acted in the heat of passion on sudden provocation in order to reduce murder to manslaughter, and the Court held that this unconstitutionally shifted to the defense the burden on the malice element of homicide.³⁰

Patterson v. New York shows what distinguishes a valid allocation from the one in Mullaney. The Maine statute presumed a lack of provocation, which the Court treated as presuming malice, while New York's definition of murder omitted malice aforethought, so extreme emotional disturbance stood as a separate affirmative defense and left the prosecution's burden on every defined element untouched.³¹ The defense of alibi falls on the Mullaney side of the line. Disproving an alibi is simply another way of proving that the defendant committed the offense, so the prosecution must carry it.³²

On an exam, the question to ask about a defense the defendant is told to prove is whether the claim adds an excuse after the elements or attacks one of them. Students lose this issue when they assume anything the legislature labels a defense can be assigned to the defendant, and they err in the opposite direction when they assume the Due Process Clause always requires the prosecution to disprove a raised defense, a reading Patterson repudiated.³³ A state that writes the absence of self-defense into its definition of the crime keeps the persuasion burden on the prosecution, although the accused may still be required to produce some evidence of self-defense before the issue goes to the jury.³⁴