precedent
1) n. a prior reported opinion of an appeals court which establishes the legal rule (authority) in the future on the same legal question decided in the prior judgment. Thus, "the rule in Fishbeck v. Gladfelter is precedent for the issue before the court in this case." The doctrine that a lower court must follow a precedent is called stare decisis 2) adj. before, as in the term "condition precedent," which is a situation which must exist before a party to a contract has to perform.
In simple terms, that means that a previous verdict influences a later one. A judge might be confused on how to decide a case, and then he thinks "Hey, so-and-so v. so-and-so was sorta like this. This could help me decide this case."
Anyway, the precedent set in Miranda v. Arizona affects laws and procedures today. The main change was that it increased police powers while making sure that basic human rights were maintained. Miranda was not advised of his right to counsel while being interrogated, and so had no lawyer with him. This was the deciding factor in why the Supreme Court ruled that you MUST be advised of your Constitutional rights before being taken into custody. Every time you are arrested, you are advised of your rights, or your confessions cannot be used against you in a court of law. This is a possible way to completely or almost completely get off without any charges. Anything you say in front of an official, if you are not read your rights, is inadmissible in court.
However, the police officer driving you to the station is under no obligation to read you your rights. The only time you can pull the "I wasn't read my rights" was if you were taken into custody and were questioned without being read your rights. The only time, I repeat, the only time that you must be read your rights is if you are about to be questioned, they must start off by reading you your rights. If they don't, then you can appeal and say that you weren't read your rights, and THEREFORE your testimony is inadmissible, whether or not you admitted guilt. If you were not read your rights prior to questioning, and if you did not have legal counsel while you were being questioned, your testimony is inadmissible because it is considered hearsay.