I widnessed a few times already that there are sometimes bonuses on CRIT roles. See image. I have seen even +2 bonuses. Where are these bonuses coming from?
I think that the reason is that Expanded Critical Hits rule is on (Tac.Op. p.74). There is a bonus on determining critical hits table depending on the damage of the weapon (6-10 +1, 11-15 +2, 16-20 +3, >21 +4). In the example you posted, it was a punch hit of 8 points (+1).