What happens to evidence if an arrest is found unconstitutional?

If an arrest is found unconstitutional, any evidence obtained as a result of that arrest may be deemed inadmissible in court under the exclusionary rule. This means that law enforcement cannot use that evidence to support a prosecution. Additionally, the defense may file a motion to suppress the evidence, arguing that it was obtained in violation of the defendant's constitutional rights. Ultimately, if the court agrees, the evidence cannot be presented during trial.