Burden of Proof

Who must prove what, and to what standard

Definition

The burden of proof is the obligation of a party to prove the disputed facts to the legal standard required to win a claim or charge. The party bringing the claim normally carries this burden, and if it fails to meet the required standard, the other side prevails. The exact level of proof needed depends on the type of case—civil cases use a lower standard than criminal cases.

Legal Meaning

The burden of proof answers two essential questions in every case: who must prove the facts, and how convincing must that proof be. The first part is sometimes called the burden of persuasion, and the second part is the standard of proof. Together they determine which party loses if the evidence is not strong enough.

In civil litigation, the plaintiff generally bears the burden of proving each element of the claim. In a criminal case, the prosecution bears the burden of proving guilt, and the defendant does not have to prove innocence—a principle that reflects the presumption of innocence and the protections of due process. A party who raises an affirmative defense, such as self-defense or the statute of limitations, usually must prove that defense.

The law recognizes three main standards of proof. The lowest, preponderance of the evidence, applies in most civil cases. The highest, beyond a reasonable doubt, applies in criminal cases. In between sits clear and convincing evidence, used in certain serious civil matters. These standards directly shape how a jury reaches a verdict and what the judge instructs the jury to find.

Key Points

  • The burden of proof sets who must prove the facts and how convincingly
  • The plaintiff bears the burden in most civil cases
  • The prosecution bears the burden in criminal cases; the defendant need not prove innocence
  • Preponderance of the evidence is the usual civil standard (more likely than not)
  • Beyond a reasonable doubt is the demanding criminal standard
  • Clear and convincing evidence is an intermediate standard for some civil matters
  • A party raising an affirmative defense usually must prove it
  • The burden of producing evidence can shift, but the ultimate burden generally does not

Real-World Example

Suppose the same conduct leads to both a criminal case and a civil lawsuit. In the criminal trial, the prosecution must prove the defendant's guilt beyond a reasonable doubt; if the jury has a reasonable doubt, it must acquit. The defendant might be found not guilty because that high standard was not met.

In a later civil suit arising from the same event, the plaintiff need only prove liability by a preponderance of the evidence—just over a 50 percent likelihood. Because that standard is lower, the defendant could be found liable in the civil case and ordered to pay damages, even after being acquitted in the criminal case. The different burdens of proof explain how the two outcomes can coexist.

The Three Standards of Proof

Standard What It Requires Typical Use
Preponderance of the Evidence More likely than not (just over 50%) Most civil cases
Clear and Convincing Evidence Highly probable Fraud, some probate, parental rights
Beyond a Reasonable Doubt Near certainty of guilt Criminal cases

How the Burden of Proof Works at Trial

The burden of proof shapes the entire trial, from who speaks first to who loses ties:

Order of Presentation

Because the plaintiff or prosecution carries the burden, that side presents its evidence first. The party with the burden must produce enough proof on every element to allow a reasonable jury to find in its favor.

Meeting—or Failing to Meet—the Standard

If the party with the burden does not meet the required standard, it loses, even if the other side offers no evidence at all. This is why a defendant can sometimes win simply by undercutting the other side's proof.

Shifting Burdens

While the ultimate burden of persuasion stays put, the burden of producing evidence can move during trial. Once one side makes a strong enough showing, the other may need to respond with rebuttal evidence to avoid losing the point.

⚠️ Important: Misunderstanding the burden of proof is a common and costly mistake. A plaintiff who cannot gather enough evidence to meet the applicable standard may lose despite genuinely being wronged. Before filing or defending a case, get an attorney's honest assessment of whether the evidence can satisfy the required standard.

Related Terms

Will the Evidence Support Your Case?

Meeting the burden of proof takes the right evidence and strategy. A qualified attorney can tell you where you stand.

Find a Lawyer Near You

When You Need a Lawyer

Whether you bring a claim or defend against one, understanding and meeting the burden of proof is central to the outcome. A lawyer can:

  • Explain which standard of proof applies to your case
  • Assess whether the available evidence can meet that standard
  • Gather and present evidence through proper discovery
  • Identify affirmative defenses and the proof they require
  • Request accurate jury instructions on the burden of proof

If your claim involves an injury, our personal injury practice area page explains how these cases are proven, and our guide on civil vs. criminal cases compares the standards used in each system.

Frequently Asked Questions

What is the burden of proof?

The burden of proof is the obligation a party has to prove the disputed facts to the level the law requires in order to win. The party making a claim usually carries this burden. If that party fails to meet the required standard, the other side prevails, even without offering evidence of its own.

Who has the burden of proof in a lawsuit?

In a civil lawsuit, the plaintiff generally bears the burden of proving each element of the claim. In a criminal case, the prosecution bears the burden of proving guilt; the defendant does not have to prove innocence. A party who raises an affirmative defense, however, usually carries the burden of proving that defense.

What is the difference between preponderance of the evidence and beyond a reasonable doubt?

Preponderance of the evidence, used in most civil cases, means it is more likely than not that a fact is true, just over a 50 percent likelihood. Beyond a reasonable doubt, used in criminal cases, is a much higher standard requiring near certainty of guilt. The criminal standard is stricter because a person's liberty is at stake.

What is the clear and convincing evidence standard?

Clear and convincing evidence is an intermediate standard that sits between preponderance of the evidence and beyond a reasonable doubt. It requires a party to show that a fact is highly probable, not merely more likely than not. Courts apply it to certain civil matters such as fraud, some probate disputes, and the termination of parental rights.

Can the burden of proof shift during a case?

The ultimate burden of persuasion usually stays with the party that started with it. However, the burden of producing evidence can shift back and forth during trial. For example, once a plaintiff presents enough evidence on an issue, the defendant may need to come forward with evidence to rebut it, even though the overall burden does not change.

This information is for educational purposes only and does not constitute legal advice. Standards of proof and how they are applied vary by jurisdiction and case type. Always consult a qualified attorney for advice specific to your situation.