The Fourth and Fifth Amendments to the U.S. Constitution protect people against misconduct by police and prosecutors. In cases of suspected driving while intoxicated (DWI), New Jersey police are bound by various decisions of the U.S. and New Jersey Supreme Courts that apply these constitutional rights. Police cannot stop a person’s vehicle, for example, unless they have reasonable suspicion of DWI or other unlawful activity, or as part of an established temporary DWI checkpoint. A decision issued by the New Jersey Superior Court, Appellate Division in September 2019 addressed a different situation, which is less common in DWI cases. Police entered the defendant’s home, questioned him there, and then arrested him for DWI. The court considered whether this violated his rights under the Fourth or Fifth Amendments.
New Jersey’s DWI statute provides prosecutors with two ways to prove that a defendant was under the influence of alcohol or other drugs. If breath, blood, or urine testing shows blood alcohol concentration (BAC) of 0.08 percent or higher, state law presumes the person to be intoxicated. Even without BAC evidence, though, police and others can testify about their observations of a defendant’s appearance, odor, and behavior, to establish intoxication.
The Fourth Amendment requires police to obtain search warrants based on probable cause. Courts have identified numerous exceptions that allow police to enter private property and conduct searches without a warrant. They must be able to convince a judge that the search fits within an identified exception. The Fifth Amendment guarantees the right against self-incrimination. Police cannot coerce a person to confess to a crime, and prosecutors cannot compel a person to implicate themselves. A defendant can challenge the constitutionality of a search or arrest by filing a motion to suppress evidence. If a judge finds a violation of constitutional rights, any evidence obtained as a result is suppressed, meaning prosecutors cannot use it at trial.