The Fifth Amendment declares that no person can be compelled to provide testimony against himself, and this typically means a person's unwillingness to do so cannot be used against him in a trial. But a June ruling by the Supreme Court puts the burden on individuals to invoke this right if they are being interviewed by police but have not yet been arrested.
Genovevo Salinas agreed to answer questions from Houston police officers investigating a murder. He was not arrested and was not read his rights. When asked questions that could implicate a shotgun he owned as the crime weapon, he clammed up. He was subsequently charged with the crime, and his silence was used by prosecutors in the trial as evidence of his guilt.
Salinas challenged his conviction as a Fifth Amendment violation. The case, Salinas v. Texas, was intended to explore whether the Fifth Amendment's protection against compelled self-incrimination applies to interviews that take place prior to an arrest. But the Court, in a 5-to-4 ruling, sidestepped that question, concluding that Salinas' silence could be used against him because he never explicitly invoked the Fifth Amendment. In his dissent, Justice Stephen Breyer noted that the decision gives mere suspects or persons of interest less protection than actual arrestees, whose silence is typically viewed as an implicit assertion of their Fifth Amendment rights.