Re: Principles of pinning
Actually Roger you are incorrect on most counts here. Law enforcement officers are taught to perform what we call pins as control holds. The purpose is to control the offender's body, usually through a limb, until he can be mechanically restrained with handcuffs or the like and safely taken into custody and confined. The purpose is not to inflict pain, although that may happen just as it does in a dojo. "Police brutality" isn't a legal term. Excessive force is the term used by the courts. The force used by a law enforcement agent only becomes excessive force if it is unreasonable or unnecessary and doesn't hinge on whether the suspect suffers an injury. The determination of whether police application of force was reasonable is based on the "reasonable peace officer" standard which means would a reasonable peace officer use the same level of force under the same circumstances? The calculus involved does not involve reviewing all force options available, but was the actual force used reasonable and necessary.
You stated that officers choose to use brute force and I disagree. They certainly will use all the help available in any force event. Each participant will still be bound by the legal and department rules regarding use of force. A point to remember is that even the most noble of officers will not play fair in a confrontation. Fair is a sporting term and there are no sporting events in a criminal apprehension. The best will use their training appropriately, lawfully and ethically, but it won't necessarily be fair. One officer can restrain a suspect successfully, but why take the chance of an error if other officers are present to assist?
We train differently in the dojo than the cops do, and far more often. What we tend to forget in the dojo setting is that every throw is a notional death and every pin is a destructive incapacitation in theory.