There is an ongoing debate about the moral duty to take action and intervene in a bad situation that doesn't directly concern us, and we can choose to participate or not. Most trainers will argue that it is not your problem and cite the risks involved in taking action.

I have seen a lot of students that have a "white hat" mentality. They believe that they have a duty to act and easy willingness to use force for the greater good, despite the cautions of the professional trainers.

The simple question is "who and how much?" If we get involved in other peoples problems we run the risk of committing to more that we really wanted to. Ultimately, If you are killed (or convicted) protecting a stranger then who will defend and provide for your spouse and/or children? What are the parameters of our obligation to others?

I generally ask the question, that if you are getting involved to save the life of an innocent third party, and saving lives is the goal - who has first aid training? Would you give mouth-to-mouth or put your bare hands on some strangers bloody wounds? Most students would refuse to do so because of the risks of infectious disease.

First Aid is very low risk in terms of legal liability and most of the US population will probably not infect you with anything. If you were really concerned with saving lives, a pocket mask and gloves weigh less than a handgun and reload.

Many of the problems that present opportunities for third party intervention are not solvable on the tactical level. If you talk to police officers about domestic disputes they will tell you that it is not uncommon for the battered woman to bail the abuser out of jail, or even fight with the police to prevent his arrest. While we might able to stop the immediate incident, we might not be able to fix the root cause. We still incur all of the liability for taking action though.

As a third part actor we will generally be operating on incomplete information. If two men are beating a third with baseball bats in a parking lot, it is clearly illegal activity and you have justification for taking action to defend the victim. Would you still be willing to take action if the 'victim' was a robber and the men with the bats were store clerks? What if this was a fight between gang members or drug dealers?

The cold-blooded answer is that if I don't know you, I don't help you. My only exposure is being able to look in the mirror and live with that decision. I would say this answer is the only correct one where you cannot make an educated guess as to who is the 'innocent victim.' If everyone looks like a bad guy, I am going to call the police and let them sort it out.

A more practical answer is to meter out my involvement. Calling the police and being a good witness is universal. Issuing verbal commands from a position of cover and distance may solve the immediate problem, while providing time to get a better assessment of the situation.

The only circumstances where it is really black and white would be going to the aid of a police officer or a child. In the case of a police officer, you need to conduct yourself in such a manner as not to be confused with the perpetrators by other responding officers.