In any criminal case, the evidence against the defendant can lead to a conviction. However, when the evidence presented by the prosecutor contains certain flaws or was unlawfully obtained, a criminal defense attorney can file a motion to suppress the evidence.
In Texas, a motion to suppress asks the judge to throw out evidence which was collected by law enforcement or a private party since it was obtained in violation of state law or the U.S. Constitution. This motion is typically filed prior to trial.
The following are the common reasons a court may suppress evidence:
- Police conducted an unlawful search and seizure – According to the Exclusionary Rule, evidence must be collected through legal search and seizure methods in order to be admissible in court. Police need to have a legitimate arrest or search warrant, or probable cause that the defendant committed a crime to lawfully gather evidence.
- Police failed to read the defendant his/her Miranda rights – Upon arrest or detainment, the defendant needs to know that he/she has the right to remain silent, that anything he/she says can be used as evidence in a court of law, and that he/she has a right to legal counsel. If law enforcement fails to read the defendant his/her Miranda warnings, anything he/she says after arrest is inadmissible.
- Broken chain of custody – From being collected by law enforcement to its presentation by the prosecutor in the courtroom, the process of documenting and preserving evidence is known as the “chain of custody”. If any part of the chain is compromised (i.e. police mislabeled blood samples, failed to perform the proper testing procedures, etc.), the evidence can be thrown out.
When a criminal defense attorney files a motion to suppress with the clerk’s office, a copy is given to the prosecutor, who has a chance to file an objection to the arguments contained in the motion. If the prosecution files a response, a court hearing will be held before a judge to determine if the evidence mentioned in the motion is inadmissible.
In most cases, a motion to suppress can lead to a dismissal. If the prosecution cannot prove the case against the defendant, the state may have no choice but to dismiss the case.