Self-defense in Virginia is an affirmative defense, the absence of which is not an element of murder. In making this plea a defendant implicitly admits the killing was intentional and assumes the burden of introducing evidence of justification or excuse that raises a reasonable doubt in the minds of the jurors.
The law of self-defense is the law of necessity, and the necessity relied upon must not arise out of defendant's own misconduct. Accordingly, a defendant must reasonably fear death or serious bodily harm to himself at the hands of his victim. It is not essential to the right of self-defense that the danger should in fact exist. If it reasonably appears to a defendant that the danger exists, he has the right to defend against it to the same extent, and under the same rules, as would obtain in case the danger is real. A defendant may always act upon reasonable appearance of danger, and whether the danger is reasonably apparent is always to be determined from the viewpoint of the defendant at the time he acted.
McGhee v. Commonwealth, 219 Va. 560, 562, 248 S.E.2d 808, (1978).

Use of Force Against Trespasser

The common law in the state of Virginia has long recognized the right of a landowner to order a trespasser to leave, and if the trespasser refuses to go, to employ proper force to expel him, provided no breach of the peace is committed in the outset...
Absent extreme circumstances, however, such force may not endanger human life or cause great bodily harm.
Pike v. Commonwealth, 24 Va. App. 373, 375-376, 482 S.E.2d 839, (1997).

Justifiable And Excusable Homicide

Justifiable homicide in self-defense occurs where a person, without any fault on his part in provoking or bringing on the difficulty, kills another under reasonable apprehension of death or great bodily harm to himself.
Excusable homicide in self-defense occurs where the accused, although in some fault in the first instance in provoking or bringing on the difficulty, when attacked retreats as far as possible, announces his desire for peace, and kills his adversary from a reasonably apparent necessity to preserve his own life or save himself from great bodily harm.
Bailey v. Commonwealth, 200 Va. 92, 96, 104 S.E.2d 28, (1958).

Virginia Law On Deadly Force To Protect Property

The threat to use deadly force by brandishing a deadly weapon has long been considered an assault.
The owner of land has no right to assault a mere trespasser with a deadly weapon. A deadly weapon may not be brandished solely in defense of personal property.
Commonwealth v. Alexander, 260 Va. 238, 241, 242, 531 S.E.2d 567, (2000).