This in from a state academy rule book on firearms training:
"SHOULDER HOLSTERS, CROSS DRAW HOLSTERS, AND HOLSTERS HAVING AN UNLOCKING DEVICE OPERATED BY THE TRIGGER FINGER, ARE PROHIBITED."
It is used to specifically exclude the Blackhawk Serpa holster from being used on their range. As with many rules, it is based on incidents that have taken place on the range during training. They observed that proper technique for this holster, finger pad used to operate the "finger activation platform," would degrade as the amount of shooter stress increased causing the finger tip to press on the platform and have a higher liklihood of causing the pistol to fire. After having this happen, this academy did a Risk Management review which resulted in the rule.
Another report had a shooter get entrance/exit wounds in both thigh and calf while drawing from this holster. The requirement after this incident was that the holster must be adjusted to a canted position, to allow rounds fired in the holster to miss the shooters body.
Blackhawk's television advertisement shows use of the finger pad, but their latest holster instructions do not mention specific technique. On the Blackhawk sales training video, Chuck Buis of Blackhawk demonstrates proper technique, but is not specific as to technique.
Most users of this holster won't be seeing that video, so it's up to firearms instructors to know about this and help where indicated.
Trainers working with governmental entities would do well to realize that training efforts may be monitored and affected by Risk Management offices. In the instance mentioned above, statewide levels of government worked with a state government Risk Management office in making the determination to forbid the use of the holster. The potential for an injury, once recognized, must be addressed. Training absent due diligence to reduce the problem can result in a lack of insurance coverage for affected parties. Most entities will look for the easiest way to reduce that risk.
The potential for the holster to pull the retention screws through and free of the belt slide or paddle, is another issue.