What is Probable Cause in a Criminal Appeal?


Probable cause is a term that is used often in criminal law and is one of the most common issues in a criminal appeal in Illinois or federal court. Probable cause allows a police officer to arrest someone or to conduct a search without an arrest warrant and it is required before a judge can issue an arrest warrant. Probable cause is also required before a grand jury can return an indictment. The requirement that police act with probable cause comes from the 4th Amendment, which states:

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

What is probable cause in a criminal appeal?

What is the Definition of Probable Cause?

Although probable cause is a term that is used often in the criminal law, it does not have a fixed definition. A common definition of probable cause used by the courts is “a reasonable amount of suspicion, supported by circumstances sufficiently strong to justify a prudent and cautious person’s belief that certain facts are probably true.” To establish probable cause, a police officer is allowed to use his or her knowledge and experience in making the determination as to whether probable cause exists. Ultimately, probable cause exists when the facts and circumstances are sufficient to warrant a prudent person to believe that a person has committed, is committing, or is about to commit a crime.

How Can Probable Cause Be Established?

Probable cause exists when the police officer has sufficient facts to justify a search and seizure. To establish probable cause the police officer’s actions must be based upon actual facts and circumstances that would lead a reasonable officer to believe that criminal activity has occurred or is about to occur.

To satisfy the probable cause requirement a police officer is allowed to his or her personal observations; hearsay statements made to the officer; the officer’s expertise; and any circumstantial evidence available at the time of the search or seizure.


Probable cause is a term that dominates 4th Amendment law. All warrantless arrests and searches are conducted based upon probable cause. A court decides whether probable cause actually existed after a suppression hearing. Evidence that was seized without probable cause is excluded and cannot be used in any future prosecution.

Probable cause is a very fact-based legal term. Case law is filled with cases that are identical that have reached a different result on the legality of a warrantless arrest or search. Most of the time, the
difference in results is the ability of the criminal defense attorney to establish a 4 th amendment violation.

Jaleel Law P.C. has the experience to properly handle suppression hearings and the know-how to present the evidence in the effective and persuasive manner. If you have been arrested for any crime without a warrant, you may have a successful suppression motion based upon a lack of probable cause. Contact Jaleel Law P.C. to discuss your situation and how we can help.

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