You have to look at it like this, shooting someone is manslaughter but the law allows several defenses for it. Self-defense is a defense to guilt. So basically, anytime you kill someone, it is considered a manslaughter unless the PA thinks it is obviously not worth the effort to prosecute, or until a jury decides that you are not guilty due to one of the defenses (such as self defense).
So during all that time between the shooting and the decision by the PA or the jury, you are technically charged with manslaughter.
I'll give you an example, a friend of mine was having a party at his house and got in a dispute with a few people who were drunk and asked to leave. They came back with weapons and he was forced to defend himself. Obviously self-defense, but he sat in jail until he was able to post bail, and the trial is set for December NEXT YEAR. So during the next year, he has "charges pending" even though his attorney basically says it is a no-brainer.
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In the beginning, the patriot is a scarce man -- brave, hated, and scorned. But when his cause succeeds, the timid join him. For then, it costs nothing to be a patriot. -- Mark Twain