After a citizen rightfully defends themselves against an armed and violent criminal, the family of that criminal or members of the media sometimes blame that citizen for shooting the criminal.  They argue that the crime victim didn’t need to use force to defend themselves, or used too much force. In almost every such situation, it is ridiculous to second guess the victim who defends themselves from a criminal, for the reasons discussed below.

First, a self defense law primer
A person can use deadly force to defend themselves when they are in reasonable fear of suffering death or grievous bodily harm at the hands of a wrongdoer.  Reasonable, non-deadly, force can be used to defend oneself or stop a crime when a person is not in fear of suffering death or grievous bodily harm. It is not lawful to use deadly force to stop a pick-pocket who is running away, but reasonable, non-deadly force could be used.  A citizen has no duty to allow a criminal to victimize them, or to cooperate with the criminal (such as by giving an armed robber one’s wallet).  A person is also justified in using the same level of force to defend another that they would be justified in using to defend themselves.  The law varies a bit between states, with some allowing more or less use of force, but the basic principles discussed above are virtually universal. [Note: This is not legal advice, but merely a discussion of facts necessary to make the points discussed below.  Read the full disclaimer here.]

Why “shooting to wound” is never appropriate
Those who are not knowledgeable about guns and human anatomy will suggest that a citizen shoot a criminal in the leg, rather than aiming for the criminal’s chest, so as to avoid killing the criminal, even when the citizen’s life is threatened.  That is bad advice. The only way to reliably stop a violent human right away is to disrupt the brain, spine, heart, or certain other vital organs.  Even severe bullet wounds to the lung(s) generally won’t stop an attacker right away, as there is enough oxygen in the blood stream that they can keep up their attack for about 30 seconds. This means that shooting only to wound is never appropriate, as a gunshot wound to the leg/arm/stomach will not stop the criminal from continuing their attack (although it might kill them minutes, hours, or days later).  The law strongly disfavors shooting to wound, and it as often seen as evidence that the citizen was not in reasonable fear of suffering death or grievous bodily harm, (and any gunshot can be fatal so it is not possible to truly shoot only to wound).

The pressure which violent crime places upon the victim
A citizen who is suddenly faced with an armed robber or other dangerous criminal is caught off guard and has little time to think.  They are faced with the prospect of being murdered or permanently disabled by the violent act of a criminal.  All too often, they also face the very real possibility that a spouse/child/friend will be murdered or raped by that criminal too.  For many crime victims, this is a new experience that they are ill prepared to handle; and even those who have suffered violent crimes before are little better off (indeed such people may be traumatized even more by being made a repeat crime victim).  The net result is that crime victims are terrified, and have adrenaline rushing through their bodies.  They know that they have just a brief time to decide what to do, and that the consequences of failing are dire.  It is against this backdrop that the actions of a crime victim who defends themselves should be analyzed.

Why it is wrong to second guess crime victims who use force to defend themselves
As discussed above, crime victims are suddenly thrust into a dangerous situation that is not their fault, and are under tremendous stress.  They have to make a life or death decision in little time, for criminals tend to be ruthless and will not hesitate to kill an innocent citizen.  Therefore, it is simply wrong for people to play “Monday morning quarterback” and second guess a citizen who used deadly force to defend themselves against a violent criminal.  No one but that citizen knows how things really went down.  No one but that citizen saw the subtle movements and body language of the criminal, or other factors that play a huge role in how humans convey and interpret threats.  No one but that citizen faced that threat and felt that fear, which is unique to each individual and each situation. No one but that citizen was faced with the risk that that criminal’s actions would kill or seriously injure them.
In an ideal world, there would be no crime.  In a slightly less ideal world, there would exist a weapon that could incapacitate a criminal without harming them.  Such a weapon (and no, Tasers are not this weapon) would allow the police to come and apprehend the criminal, with no loss of life.  However we don’t live in such an ideal world, and the only way to reliably stop a criminal before they can inflict death or grievous bodily injury tends to be shooting them in a way that is also fatal.  If someone must suffer death, it is far better that the violent criminal is the one who suffers, rather than their innocent current victim and future victims.

An example: The self defense shooting of Brandon Starks
As reported, Brandon Starks was a 20 year old criminal who had just been paroled from prison after serving time on a burglary conviction.  Starks went to the People’s Market in Waukeegan, IL armed with a gun.  Starks then used the gun to threaten the life of the store clerk and commit armed robbery.  The clerk grabbed his own gun and fatally shot Brandon Starks seconds after the robbery, in front of the store.
Veda Starks, Brandon Starks’ mother, then had the audacity to condem the clerk who shot her (burglary and armed robbery committing) son.  The clerk was faced with a gun toting convicted felon, and used a gun in self defense.  The clerk had no duty to allow that criminal to rob him, or threaten his life.  Nor is it proper for individuals who were not there, and who were not in fear of being shot by a convicted felon, to scrutinize the actions of that store clerk.  For example, Starks could have come back in the store seconds later to shoot the clerk to avoid being identified.  Starks could have fired after leaving the store, just as a criminal fired after leaving a bus, killing this girl.  Or, the clerk could have been attempting to use reasonable force to prevent Starks from escaping with the money (as is the clerk’s legal right) when Starks again placed the clerk in reasonable fear of death or grevious bodily injury, thereby justifying the use of deadly force on the part of the clerk.  There are many other scenarios I could list, but the point is that Starks was in the wrong, while the clerk was just trying to go about his lawful business.  Fault for the death of Brandon Starks lies firmly with Brandon Starks for choosing to rob and threaten the life of an innocent man.  Brandon Starks paid the price for his criminality – and based upon Stark’s repeated commission of felonies, the store clerk likely prevented other people from suffering at Stark’s hands in the future.