1. A method for setting a threshold in a biometric system by using imposter match score data to derive a match threshold score that results in a desired false match rate comprising: creating a database of match scores between all unique impostor biometric sample pairs; creating, using a processor, a cumulative histogram data table that records, for each possible match score outcome, a number of match scores observed greater than the threshold divided by the total number of samples; using the cumulative histogram data table to determine the threshold; selecting the desired false match rate and determining the threshold that will result in the desired false match rate; and determining a false match probability level.