Method performed by a computer system for biometric authentication of human beings of a first or a second category

[0067] Method performed by a computer system (1) for biometric authentication. The method comprising the steps of retrieving a first fingerprint data (12) alleged to be of the first human (6) and retrieving a second fingerprint data alleged to be of the second human (9). If the retrieving of the first fingerprint data (12) is conducted within a first predetermined time interval (17) from the retrieving of the second fingerprint data (14), comparing the retrieved first fingerprint data (12) and the retrieved second fingerprint data (14) to the stored fingerprint data (8) of the first (6) respectively the second human (9). Providing a positive indication (15) when a match is confirmed for both the first fingerprint data (12) and the second fingerprint data (14) compared to the stored fingerprint data (8) of the first (6) respectively the second human (9).