The amount of evidence which a plaintiff (or prosecuting attorney, in a criminal case) must present in a trial in order to win is called the standard of proof. Different cases require different standards of proof depending on what is at stake. The common standards are:
- Beyond a reasonable doubt (criminal cases)--for a criminal defendant to be convicted of a crime, the prosecutor must prove her case to the point that the jurors have no reasonable doubts in their minds that the defendant did whatever he is charged with having done.
- Clear and convincing evidence (civil cases involving the potential loss of important interests such as the termination of parental rights)--for a party to prove a case under this standard, she must show something more than it is more likely than not, but not as much as beyond a reasonable doubt. No legal scholar has ever been able to define clear and convincing evidence more precisely than that.
- Preponderance of the evidence (most civil cases including fault divorces)--preponderance of the evidence generally means that a party will win if she can show that it is more likely than not that her contention is true.