Every state and the District of Columbia has its own criminal procedure codes. However, each of these jurisdictions must act in compliance with the U.S. Constitution.
Each state’s rules and regulations on criminal procedure codes are predicated on the Federal Rules of Criminal Procedure. The Constitution contains numerous provisions to protect individuals arrested for a crime and individuals who are suspected of having committed a criminal offense.
In order to arrest a suspect, the police must have probable cause — which means that they possess enough evidence to indicate that the person is likely to have committed a crime. Police suspicions about the commission of a crime are not enough to permit an arrest.
In many cases, police officers must obtain an arrest warrant from a judge after offering their evidence of probable cause. Obtaining an arrest warrant is not possible in all cases, so there are exceptions to warrant policies. For example, an individual may be arrested without warrant if a police officer witnesses him or her committing a crime.
Additionally, an individual cannot be subjected to a police search of home, car or person unless the officers have probable cause. Without such justification, any evidence police obtain in their search may be thrown out of court. In most cases, a legal search is only possible with a warrant issued by a judge. Again, there are exceptions to the search warrant rule. If a person invites an officer into a home, for example, that officer may seize any evidence in plain sight.
Should a person be taken into custody, he or she cannot choose to leave that custody — particularly if he or she has been taken to a police station for questioning. Questioning may not begin until the individual is read his or her Miranda rights and advised about the ability to ask for a lawyer at any time. If a suspect’s rights are violated in any manner, nothing said can be used in court.
A suspect does not automatically go to court. If a person pleads not guilty, a preliminary hearing decides the court route the case will take. In a preliminary hearing, the prosecutor offers evidence and presents the case for the suspect’s guilt. The criminal defense lawyer counters those arguments and tries to attack the prosecution’s evidence. The final disposition of the case is up to the judge. Depending on the jurisdiction, some states only hold a preliminary hearing if the accused is charged with a felony. Other states prefer to use grand juries.