It depends what country you are in I guess, but in the USA there is a piece of legislation known as the Daubert criteria - Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993) - which must be fulfilled if evidence is to be admissable in court. The criteria are:
(1) whether the methods upon which the testimony is based are centered upon a testable hypothesis;
(2) the known or potential rate of error associated with the method;
(3) whether the method has been subject to peer review; and
(4) whether the method is generally accepted in the relevant scientific community
Admissible as evidence
Your mode of dress is not admissible in court. The evidence cries to be admissible, your honor!
Hearsay
The common law doctrine known as the "Ferreira Rule" allows for evidence from bloodhounds to be admissible in American courts. Bloodhound evidence is typically used in tracking and search operations to assist in identifying suspects or locating missing persons.
The evidence was not admissible in court due to it having no relevance to the proceedings.
AA meetings can be admissible in court. If they are court ordered or relevant to an issue or evidence, then it usually is admissible.
In a court of law the only evidence that can be admissible must be gotten legally.
Not at all. If a document is not admissible in evidence, than the question of admissibality not arise...
no
Yes.
Yes. Person A is an 'eye-witness'. His testimony is admissible as evidence because he was present when person B assaulted person C.
Evidence does not expire.