If Massachusetts law enforcement charges you with a crime, they must conduct their investigation correctly and legally. They have to inform you of your rights and obtain warrants to search your car or home.
Sometimes, the authorities make mistakes and thus invalidate their findings. Evidence gathered illegally is inadmissible in court.
How can police obtain evidence illegally?
FindLaw outlines several conditions that can make evidence against you inadmissible, and most involve violating your constitutional rights.
Law enforcement must adhere to a process referred to as the “chain of custody” to preserve the integrity of evidence. If they miss a step or otherwise break the chain, the court assumes the possibility that the evidence is not reliable and may suppress it.
The Fourth Amendment shields you from unlawful search and seizure of evidence. In almost all circumstances, the authorities must have probable cause or a properly ordered warrant before they can search your person, car or home.
When law enforcement officers put you under arrest, they are legally required to inform you of your “Miranda rights.” If the authorities interview you without reading Miranda, they violate your Fifth Amendment rights.
What happens to illegally obtained evidence?
If you believe that officers violated your rights while gathering evidence, your lawyer can file a motion with the court to suppress it. If the judge rules in favor, the Exclusionary Rule will forbid the prosecution to use the evidence in the case against you. Furthermore, the “fruit of the poisonous tree” principle can exclude all the additional evidence that resulted from the original suppressed piece of evidence.
However, there are exceptions. Prosecutors can retain evidence if the judge believes that officers acted in good faith. In other words, they believed wholeheartedly and without a doubt that they correctly followed all of the legal guidelines when they found the evidence. Evidence can also still be valid if the prosecutor can prove that the authorities would have eventually found it by inevitable discovery or from an independent source.