A false arrest is the unreasonable seizure of someone's personality. A seizure is considered unreasonable when there is a lack of probable cause to support it.When someone is arrested without property authority or without adequate evidence, then that is a false arrest. To have a claim for false arrest, you must be able to show that you were in fact arrested and that there was no probable cause. What Is False Arrest? In a false arrest case, injuries sustained aren't always physical; they can also be emotional or psychological. You can only be detained or arrested in this country if there is probable cause on behalf of the police to do so. Personal Injury Attorney Steve Williamson answers the question, "What is the definition of a false arrest? A police officer must have probable cause to believe that a person has committed a crime for the arrest to be proper. Fee Structure: We operate on a contingency fee basis for false arrest cases.