How to challenge probable cause?
Asked by: Carmel Armstrong | Last update: February 4, 2026Score: 4.3/5 (70 votes)
To challenge probable cause, a defense attorney files a motion to suppress evidence, arguing law enforcement lacked sufficient facts for an arrest or warrant, often by attacking the affidavit's basis, informant credibility, or police conduct, aiming to exclude illegally obtained evidence, which can lead to case dismissal or reduced charges, notes Lewis & Dickstein, P.L.L.C., Zaki Ali, Trial Lawyers, and Bruno Lilly LeClere, PLLC.
How to defend against probable cause?
Protecting Your Rights Against Probable Cause Violations: Consult a California Criminal Defense Attorney. If you believe that your rights have been violated due to a lack of probable cause, it is crucial to consult with a criminal defense attorney who can help you navigate the complexities of your case.
What evidence do you need for probable cause?
Probable cause exists when the facts and circumstances within an officer's knowledge would lead a reasonable person to believe that a crime has been committed (for an arrest) or that evidence of a crime is present in a specific location (for a search).
What are the 4 types of probable cause?
The four major sources for establishing probable cause are Personal Observation, Information (from informants, victims, etc.), Evidence (like items in plain view or found through expertise), and sometimes Association with known criminals in criminal settings, all pointing to a fair probability that a crime occurred or evidence exists, requiring more than just suspicion for arrests or searches.
Is probable cause enough to convict?
Probable cause only relies on having enough evidence to suspect you of a crime, not necessarily to convict you. Once the probable cause standard is met, the job of your defense attorney is to show that whatever evidence exists is not enough to convict you beyond a reasonable doubt.
The Defendant's Guide to Probable Cause | Attorney911
Can you challenge a probable cause finding?
You Can Challenge Probable Cause in a Criminal Case
If you believe that the police officer lacked probable cause for an arrest, your attorney can file a motion to dismiss for lack of probable cause. You can challenge the legal grounds and factual basis for probable cause.
What is the burden of proof for probable cause?
The burden of proof for establishing probable cause does not demand absolute certainty or conclusive evidence of criminal activity. Rather, it requires a reasonable basis or suspicion backed by factual evidence that would lead a prudent person to believe that a crime has been, is being, or will be committed.
How does a judge determine probable cause?
Determining Probable Cause
They need to have objective evidence that indicates the suspect's responsibility for the crime. Even if a police officer believes that they have probable cause, a judge may not necessarily agree. They will review the information in the affidavit for the warrant and make a final decision.
What doesn't count as probable cause?
Key Points to Understand About Probable Cause
This belief must be grounded in facts, observations, or information rather than just a vague hunch. Based on Facts: The belief must be based on factual evidence or circumstances observed by the officers. It can't be based solely on an officer's subjective opinion.
How long can you be held on probable cause?
This “48-hour rule” means that within two days, you must either be charged with a crime or let go. However, there are a few exceptions that may allow the police to hold you for more than 48 hours, such as if you're arrested on a warrant from another county or if a judge grants a special extension.
Can screenshots of messages be used as evidence?
Yes, screenshots of messages can be used as evidence, but they are often considered weak or unreliable on their own because they can be easily edited, cropped, or taken out of context, making them difficult to authenticate; courts prefer original messages with complete metadata (dates, times, sender info) and often require extra proof, like testimony or forensic analysis, to confirm they are genuine.
What is the biggest mistake in custody battle?
The biggest mistake in a custody battle is losing sight of the child's best interests by letting anger, revenge, or adult conflicts drive decisions, which courts view negatively, but other major errors include badmouthing the other parent, failing to co-parent, poor communication, violating court orders, and excessive social media use, all damaging your case and your child's well-being.
What is the hardest thing to prove in court?
The hardest things to prove in court involve intent, causation (especially in medical cases where multiple factors exist), proving insanity, and overcoming the lack of physical evidence or uncooperative victims, often seen in sexual assault or domestic violence cases. Proving another person's mental state or linking a specific harm directly to negligence, rather than underlying conditions, requires strong expert testimony and overcoming common doubts.
What not to say to the judge?
You should not say anything sarcastic, interrupt the judge, lie, use slang, make personal attacks on others, guarantee outcomes, or speak about things not relevant to the case; instead, remain respectful, address the judge as "Your Honor," answer only the question asked, and be direct and truthful to maintain credibility.
What are the three excuse defenses?
Excuse defenses—insanity, infancy, and intoxication—reflect a core principle of criminal law: a defendant's moral blameworthiness depends not only on wrongful conduct but also on the capacity to understand and choose law-abiding behavior.
What are the four sources of probable cause?
The four major sources for establishing probable cause are Personal Observation, Information (from informants, victims, etc.), Evidence (like items in plain view or found through expertise), and sometimes Association with known criminals in criminal settings, all pointing to a fair probability that a crime occurred or evidence exists, requiring more than just suspicion for arrests or searches.
Can cops just make up probable cause?
To establish probable cause, police officers must be able to point to objective circumstances leading them to believe that a suspect committed a crime. A police officer can't establish probable cause by saying something like, "I just had a hunch that the defendant was a burglar."
What is an example of a lack of probable cause?
We commonly see a Lack of Probable Cause arise in Driving Under the Influence cases in California. Law enforcement officials are constantly on the lookout for impaired drivers, especially at certain locations and during holidays, weekends, and late nights.
How to beat probable cause?
How can probable cause be challenged in court? Challenging probable cause in court involves demonstrating that the evidence used to establish probable cause was insufficient or improperly obtained.
What is rule 42 of the Rules of Court?
A Petition for Review under Rule 42 of the Rules of Court is the mode of appeal taken to the Court of Appeals (CA) from a decision or final order of the Regional Trial Court (RTC) rendered in its appellate jurisdiction.
What are the two types of determination of probable cause?
There are two kinds of determination of probable cause: executive and judicial. The executive determination of probable cause is one made during preliminary investigation.
What are the three burdens of proof?
The three main burdens (or standards) of proof in law, from lowest to highest, are Preponderance of the Evidence, required for most civil cases (more likely than not); Clear and Convincing Evidence, used in certain civil matters needing higher certainty; and Beyond a Reasonable Doubt, the strict standard for criminal convictions, meaning near-certainty of guilt.
Are allegations not evidence?
The basic rule is that mere allegation is not evidence and is not equivalent to proof. Charges based on mere suspicion and speculation likewise cannot be given credence.
How much evidence is needed to prosecute?
“Beyond a reasonable doubt” is the highest standard of proof in the UK legal system and the threshold required for a criminal conviction. This means the prosecution must present evidence so compelling that no reasonable person would hesitate to find the defendant guilty.