Gun control advocates like to point to the FBI’s civilian “justifiable homicide”table in the Uniform Crime Reports series. This is very misleading, because this only includes those killings that are initially identified by the police as justifiable homicide. A shooting might be charged as murder, or manslaughter, and then reclassified as justifiable homicide during the police investigation, or while the district attorney is considering the case. The grand jury might refuse to issue an indictment, or at trial, either the judge orthe jury might rule the killing justifiable.
Also, look at the FBI's manual on reporting justifiable homicides on p. 17:
Justifiable homicide, by definition, occurs in conjunction with other offenses. Therefore, the crime being committed when the justifiable homicide took place must be reported as a separate offense. Reporting agencies should take care to ensure that they do not classify a killing as justifiable or excusable solely on the claims of self-defense or on the action of a coroner, prosecutor, grand jury, or court.