Search Warrants and Probable Cause

One of the bedrock principles of our court system is the guarantee that people should be free from unreasonable searches and seizures. It's enshrined in our Bill of Rights as the Fourth Amendment to the United States Constitution. Every state, including Missouri, has a similar guarantee in their own state constitutions. But what does it really mean?

For everyone who's watched any television, the police are not allowed to enter and search your home without a search warrant. Contrary to what it looks like on TV, this isn't just a type-written piece of paper printed off at the police station. It's a type-written piece of paper printed off at the police station which is later signed by a judge. It might seem like a trivial step, but rest assured. It's a meaningful one.

In order for the police to search your home, they must establish "probable cause" to believe that contraband or evidence of a crime will be found there, given the facts they know at the time and the circumstances they can describe to the court. This recitation of facts will come in the form of a sworn affidavit from an investigator with knowledge of the case who promises to tell the truth.

But what if he lies? And, what if he knows it too? Perjury is an authorized penalty, but it's rarely proven and even more rarely enforced. The remedy, for most people, is filing a motion to suppress the evidence found from being used at your trial. Courts have held that this is our most effective means to discourage law enforcement personnel from fabricating bogus excuses to search your home without proper justification. If the prosecutor can't present the evidence to a jury the investigators found at your home, then that leaves them with a much weaker case.

Make sure your attorney combs through the search warrant and the supporting affidavit to see whether law enforcement had a sufficient basis of knowledge for their theory and whether they described it to the judge with enough specificity.