It's common knowledge that "hearsay" is not allowed in court, but not many people know there is a major exception used frequently to convict criminal defendants based on their own alleged statements.
First, let's define hearsay. The textbook definition of hearsay is an "out-of-court statement offered to prove the truth of the matter asserted." This definition is confusing to many people—even lawyers. Essentially, hearsay is any statement that is not made by a witness testifying under oath at a trial or hearing, when the statement is presented to prove the truth of any fact. The general idea is that you can't trust statements of fact that are made by people who are not in court, testifying subject to penalty of perjury.
Here is an example of how the hearsay rule works. Imagine that a drifter claims that he observed you dumping a body in an alley in downtown Las Vegas. The drifter reports this to police, and you are charged with murder. The drifter can show up and testify under oath to this fact at your trial. But let's say the drifter doesn't show up for trial. Can a police officer testify at your trial and repeat what the drifter claimed to have seen? No. The drifter's statement to police would be an out-of-court statement, not made under oath at trial, and the prosecution would be offering the drifter's statement as the truth. Therefore the police officer's statement would be barred by the hearsay rule. But there are many exceptions to the hearsay rule.
One of the most significant exceptions to the hearsay rule in criminal cases—one that surprises many of my clients—is NRS 51.035(3)(a), which allows the defendant's own out-of-court statements to be used against him at trial. Specifically, NRS 51.035(3)(a), declares that a statement that would otherwise be hearsay is allowed if "[t]he statement is offered against a [defendant]" and the statement is the "[defendant's] own statement, in either the party's individual or a representative capacity."
In practice, this exception allows police officers, jailhouse snitches, or anyone else to testify at your trial that you admitted to committing a crime—even if the statement has not been recorded and there is no other independent evidence of the supposed admission's accuracy. This is a rule that literally allows witnesses (e.g. the aforementioned jailhouse snitches) to make up false "confessions" so long as they are willing to lie under oath. A "confession" is powerful evidence in a trial, and as you might imagine, prosecutors make use of this hearsay exception frequently to obtain convictions in criminal trials.
Of course, there are strategies that a criminal defense attorney uses to attack a false or otherwise inaccurate confession. Some witnesses, such as jailhouse snitches, lack credibility, and may be inventing a confession in order to bargain with the district attorney for a lighter sentence. Other witnesses may be biased against the defendant to the extent they would lie under oath. Police officers may have reported certain statements inaccurately, as they often write supposed quotes from the defendant from memory in their reports, hours or days after the fact, without the benefit of a recording when it would have been feasible to record the defendant's interrogation. Moreover, statements to a police officer may be suppressed, regardless of their accuracy, if the police officer failed to properly inform the suspect, prior to interrogation, that he was not obligated to make any incriminating statements.
As always, these are only the basics. So if you have been accused of a crime based on a false or inaccurate "confession," call me today to discuss the particulars of your case.