In criminal law, an alibi defense is where you present evidence that you could not have committed the crime of which you are accused because you were somewhere else when the crime occurred. For example, the crime happened Monday night in Los Angeles – but you show that you were actually in San Francisco at that very time.
Evidence to support an alibi defense can take the form of
- eyewitnesses,
- video surveillance footage, or
- documents such as credit card receipts, workplace timecards, or hotel reservations.
An alibi defense is recognized as a valid defense in all jurisdictions in the U.S., and if successful, the defense can result in an acquittal of all criminal charges.
Examples of the defense include:
- an accused saying that he could not have committed trespass because he was with his wife at dinner when the offense occurred
- a defendant asserting that he did not rape a woman since he was out of town for work when the alleged crime took place
- challenging a battery charge by showing that a person was at a movie when the victim was hit
In most jurisdictions, defendants have to provide prosecutors with written notice that they intend to present an alibi defense. A failure to do so often precludes the accused from raising the defense.
If a defendant does raise the defense during trial, a prosecutor can try to refute it by:
- showing that the accused never gave notice of the defense, and/or
- challenging any evidence (for example, physical evidence or witness testimony) that the defendant presents to support his/her alibi.
Our California criminal defense attorneys will address the following in this article:
- 1. What is the alibi defense in criminal law?
- 2. What are some examples of alibi?
- 3. How might a prosecutor try to refute an alibi defense?
- 4. What is the law in California?

An alibi is a defense whereby defendants present evidence that they could not have committed a crime because they were somewhere else when the crime occurred.
1. What is the alibi defense in criminal law?
The legal defense of alibi means that a defendant was not present:
- at the scene of the crime, or
- at the time of the alleged offense.1
If successful, the defense works to acquit a defendant of a criminal charge.
Note that alibi is distinctive from most other defenses used in criminal law in so far that it is not an affirmative defense.
An affirmative defense, like self-defense or duress, requires a defendant to prove that the defense is applicable to a given charge. An accused must prove this by a “preponderance of the evidence.” This means it is more likely than not that the defendant has a valid defense.
The defense of alibi, though, is not an affirmative defense. A defendant does not have the burden to prove an alibi. An accused merely asserts the defense to raise a reasonable doubt as to whether the defendant could have been the one who committed the crime.2
In order to present a successful alibi, the defendant’s attorney:
- presents some evidence for the purpose of showing that the defendant was not present at the specific place of a crime and at the time of the crime, and
- attempts to show that the evidence creates a reasonable doubt as to whether the defendant was present at the time of the crime, thus requiring the defendant be found not guilty of the crime.3
2. What are some examples of alibi?
The following are a few examples of when the alibi defense is and is not successful.
Note that an alibi is more likely to succeed when an accused can corroborate it with other evidence, like:
- alibi witnesses or other defense witnesses,
- photos,
- surveillance video, and/or
- receipts.
Example: Law enforcement charge Daniel with the crime of attempted murder of his business partner. However, Daniel’s alibi that he was at his nephew’s birthday party when the crime took place is corroborated by the witnesses and other evidence. This evidence will likely be sufficient to refute the prosecution’s case against him.
Example: Molly and Andrew are charged with criminal conspiracy for plotting a robbery of a local bank. Molly attempts to raise an alibi defense by claiming she was not in the getaway vehicle with Andrew. However, Molly is still convicted of the conspiracy charge because she already made an agreement with Andrew to commit the crime.
Example: Violet is arrested for the crime of burglary, which typically involves a defendant entering a structure with the intent to commit a theft or any felony inside. But Violet produces a Miami hotel receipt and presents surveillance video from the hotel lobby showing her checking into the hotel at the time the burglary took place. This evidence will likely exonerate Violet from the burglary charges.

A prosecutor can attempt to challenge an alibi defense by giving the disclaimer that the defendant never gave notice that he/she was going to raise the defense. This is why it is essential to have a capable attorney by your side.
3. How might a prosecutor try to refute an alibi defense?
There are two common ways that a prosecutor can try to refute an alibi defense. These are by the prosecution:
- showing that the defendant never gave notice of alibi as a defense, and
- questioning the accused’s alibi witnesses and questioning their credibility.
3.1. Defendant did not disclose the defense
A prosecutor can attempt to challenge an alibi defense by giving the disclaimer that the defendant never gave notice that he/she was going to raise the defense.
Under the rules of criminal procedure in most jurisdictions, a defendant has to provide the prosecution with written notice that he/she intends to raise alibi as a defense.
The defendant’s notice must include:
- an explanation of the defendant’s presence at the time of the crime, and
- what witnesses (and the addresses of the witnesses) and/or what evidence the accused will present to support the alibi.4
If the defendant does not provide this notice, he/she is precluded from raising an alibi defense.
3.2. Question witnesses and challenge credibility
If a defendant presents alibi witnesses, a prosecutor can ask them questions with regards to the alibi. They usually try to elicit answers that cast doubt on the defense.
One common technique in rebuttal of the defense is to ask questions that may undermine a witness’ credibility. For example, a prosecutor might try to show that a witness close to the defendant (for example, a family member) is lying in order to protect the defendant.
If the prosecutor is successful, then a judge or jury will usually not believe that the witness is truthful and will not buy into the defense as a whole.
Prosecutors can also try to challenge any physical evidence that the defendant presents. For example, if an accused presents video in support of an alibi, a prosecutor can try to show that the video does not depict the defendant.
4. What is the law in California?
California criminal law recognizes the alibi defense as a valid defense in a criminal case.5
Note that it is not necessary that an accused proves an alibi. Alibi evidence only needs to raise a reasonable doubt that the defendant was not present at the scene of the crime.6
Per Penal Code 1054.3 PC, defendants in California criminal actions must provide prosecutors with:
- the names of any witnesses that they intend to call (including a description of what they intend to testify about), and
- any real evidence which the defendant intends to offer in evidence at the trial.7
For additional help…

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For additional guidance or to discuss your case with a California criminal defense lawyer, we invite you to contact our law firm at the Shouse Law Group. Our attorneys provide both free consultations and legal advice you can trust.
Our lawyers also represent clients throughout California State, including those in Los Angeles, Orange County, and San Diego.
Legal References:
- Black’s Law Dictionary, Sixth Edition – “Alibi.” See also Commonwealth v. Warrington, 326 A.2d 427 (1974).
- See, for example, In re Corey (1964) 230 Cal.App.2d 813.
- Black’s Law Dictionary, Sixth Edition – “Alibi.”
- See, for example, Federal Rule 12.1 Notice of an Alibi Defense. Rule 12.1 (a)(1): “Government’s Request. An attorney for the government may request in writing that the defendant notify an attorney for the government of any intended alibi defense. The request must state the time, date, and place of the alleged offense.”Rule 12.1 (a)(2): “Defendant’s Response. Within 14 days after the request, or at some other time the court sets, the defendant must serve written notice on an attorney for the government of any intended alibi defense. The defendant’s notice must state: (A) each specific place where the defendant claims to have been at the time of the alleged offense; and (B) the name, address, and telephone number of each alibi witness on whom the defendant intends to rely.”
- See, for example, CALCRIM No. 3400 – Alibi. Judicial Council of California Criminal Jury Instructions (2020 edition).
- See same. See also In re Corey, supra.
- California Penal Code 1054.3 PC.