Constitutional protection of accused persons - Burdens of proof and persuasion

Learning Outcomes

After reading this article, you will be able to explain the constitutional rules governing burdens of proof and persuasion in criminal cases. You will understand the presumption of innocence, the prosecution’s burden to prove guilt beyond a reasonable doubt, the allocation of burdens for affirmative defenses, and how these principles are tested under the Due Process Clause. You will be able to apply these concepts to MBE-style questions.

MBE Syllabus

For MBE, you are required to understand how the Constitution protects accused persons through rules about proof and persuasion in criminal cases. This article covers:

  • The presumption of innocence and its constitutional basis.
  • The prosecution’s burden to prove every element of a crime beyond a reasonable doubt.
  • The allocation of burdens for affirmative defenses (e.g., insanity, self-defense).
  • The Due Process Clause as the source of these protections.
  • The effect of improper jury instructions on burden of proof.
  • The distinction between elements of the offense and affirmative defenses.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

  1. In a criminal trial, which party bears the burden of proving the defendant’s guilt beyond a reasonable doubt?
    1. The defendant
    2. The prosecution
    3. The judge
    4. The jury
  2. The Due Process Clause requires the prosecution to prove which of the following beyond a reasonable doubt?
    1. Only the actus reus
    2. All elements of the charged offense
    3. All affirmative defenses
    4. Only the mens rea
  3. If a state law requires the defendant to prove insanity by a preponderance of the evidence, is this allocation of burden constitutional?
    1. Yes, for affirmative defenses
    2. No, the prosecution must always disprove insanity
    3. No, the defendant must prove insanity beyond a reasonable doubt
    4. Yes, but only in federal court
  4. Which constitutional provision is the primary source of the requirement that the prosecution prove guilt beyond a reasonable doubt?
    1. The Equal Protection Clause
    2. The Due Process Clause
    3. The Privileges and Immunities Clause
    4. The Sixth Amendment

Introduction

The Constitution protects accused persons in criminal cases by setting strict requirements for how guilt must be established. The most fundamental protection is the presumption of innocence, which ensures that the prosecution must prove every element of a charged crime beyond a reasonable doubt. These requirements are rooted in the Due Process Clause of the Fifth and Fourteenth Amendments. Understanding how burdens of proof and persuasion are allocated is essential for answering MBE questions on criminal procedure.

Key Term: Burden of Proof
The obligation to present evidence to establish a fact in dispute. In criminal cases, the prosecution bears the burden of proof for every element of the offense.

Key Term: Burden of Persuasion
The obligation to convince the factfinder (jury or judge) that a fact is true to the required standard (e.g., beyond a reasonable doubt).

Key Term: Presumption of Innocence
The principle that every criminal defendant is presumed innocent until proven guilty by the prosecution.

Key Term: Affirmative Defense
A defense raised by the defendant that, if proven, can excuse or justify otherwise criminal conduct (e.g., insanity, self-defense).

Key Term: Due Process Clause
The constitutional provision (Fifth and Fourteenth Amendments) that guarantees fair procedures, including the requirement that the prosecution prove guilt beyond a reasonable doubt.

The Presumption of Innocence

Every criminal defendant is presumed innocent. This presumption is not merely a formality—it is a constitutional right. The prosecution must overcome this presumption by proving the defendant’s guilt beyond a reasonable doubt.

The Prosecution’s Burden

The Due Process Clause requires the prosecution to prove every element of a charged crime beyond a reasonable doubt. This includes both the act (actus reus) and the mental state (mens rea), as well as any statutory elements such as causation or attendant circumstances.

Exam Warning
If a jury instruction allows conviction based on a standard lower than “beyond a reasonable doubt,” or shifts the burden to the defendant to disprove an element of the crime, this violates due process and is unconstitutional.

Affirmative Defenses and Allocation of Burdens

While the prosecution must prove all elements of the offense, the allocation of burdens for affirmative defenses (such as insanity, duress, or self-defense) is different. States may require the defendant to prove an affirmative defense by a preponderance of the evidence, unless the defense negates an element of the crime.

  • If the defense directly negates an element (e.g., lack of intent), the prosecution must prove the element beyond a reasonable doubt.
  • If the defense is “affirmative” (e.g., insanity, duress), the state may place the burden of proof on the defendant.

The Standard: Beyond a Reasonable Doubt

“Beyond a reasonable doubt” is the highest standard of proof in law. The prosecution must meet this standard for every element of the crime. The judge must instruct the jury accordingly. Failure to do so is reversible error.

Jury Instructions and Constitutional Error

If a jury is instructed that the defendant must prove an element of the crime, or that the prosecution need only prove an element by a preponderance of the evidence, this is a violation of the Due Process Clause. Mandatory presumptions that shift the burden to the defendant on an element of the offense are unconstitutional.

Burden of Proof for Defenses

  • Insanity: States may require the defendant to prove insanity by a preponderance of the evidence.
  • Self-defense: States may require the defendant to prove self-defense by a preponderance of the evidence.
  • Alibi: The prosecution must always prove the defendant was present at the crime scene if presence is an element.

Worked Example 1.1

A defendant is charged with burglary. The state statute defines burglary as “breaking and entering a dwelling at night with intent to commit a felony.” At trial, the judge instructs the jury that if the defendant was found at the scene, the jury may presume he intended to commit a felony unless he proves otherwise.

Answer: This instruction is unconstitutional. The prosecution must prove every element, including intent, beyond a reasonable doubt. The instruction improperly shifts the burden of persuasion to the defendant to disprove intent, violating the Due Process Clause.

Worked Example 1.2

A defendant raises the affirmative defense of insanity. The state requires the defendant to prove insanity by a preponderance of the evidence. The defendant argues this is unconstitutional.

Answer: The allocation of the burden of proof for affirmative defenses like insanity to the defendant is constitutional. The Due Process Clause does not require the prosecution to disprove insanity unless insanity negates an element of the offense.

Revision Tip

Focus on whether the fact in question is an element of the crime (prosecution’s burden) or an affirmative defense (defendant’s burden). If in doubt, the prosecution must prove all elements beyond a reasonable doubt.

Key Point Checklist

This article has covered the following key knowledge points:

  • The presumption of innocence is a constitutional right in all criminal cases.
  • The prosecution must prove every element of a charged crime beyond a reasonable doubt.
  • The Due Process Clause is the source of this requirement.
  • Affirmative defenses may be allocated to the defendant to prove by a preponderance of the evidence.
  • Jury instructions that shift the burden of persuasion on any element of the offense to the defendant are unconstitutional.
  • The prosecution does not have to disprove every possible defense, only those that negate an element of the crime.

Key Terms and Concepts

  • Burden of Proof
  • Burden of Persuasion
  • Presumption of Innocence
  • Affirmative Defense
  • Due Process Clause
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