Self-defense is a constitutional right
So holds State v. Hull (Wash. Ct. App. Dec. 18, 2014) (nonprecedential), in an interesting and pretty detailed opinion.
Generally speaking, courts rarely have to decide whether there is a constitutional right to self-defense, since all states generally recognize a statutory or common-law right to use force against another person in self-defense. And while there are constraints on this right - e.g., you can't use deadly force against a relatively minor attack, some states bar deadly force when there is a completely safe avenue of retreat available, and so on - a constitutional right to self-defense is unlikely to be absolute. Traditionally accepted limitations on self-defense are likely to be seen as limiting any such constitutional right as well.
But sometimes self-defense law contains substantial gaps (perhaps unintended by the legislature). One such gap is that many state penal codes - including, apparently, in Washington - expressly provide for self-defense only against people and not against animals. And in State v. Hull, the prosecution actually argued that "Self-defense is a defense to the use of force against a person, not an animal," so Hull "was not entitled to a self-defense instruction." "The language of the Washington Pattern Instruction 17.02," the prosecution argued, "is … clearly limited to lawful 'force upon or toward the person of another.' Simply put, a dog is not a 'person' as contemplated by either the statute or the pattern instruction," so when someone is tried for injuring a dog, the jury isn't supposed to consider whether he acted in self-defense.
That can't be right, and the Washington Court of Appeals said it wasn't right. Indeed, the court said, there is a constitutional right to self-defense, for three related reasons (reason 1 got the votes of all three judges, and reason 3 and possibly reason 2 got only two votes):
1. There is a long line of state court authority recognizing a right to self-defense - and a right to defend property - under state constitutions. Twenty-one state constitutions expressly secure such rights, often using language such as this:
All men … have certain inalienable rights - among which are those of enjoying and defending life and liberty, [and] acquiring, possessing and protecting property.
And while Washington doesn't have such a provision in its constitution, Washington courts have recognized such a right in the context of defending property against animals (even when killing the animal might violate game laws or other laws). [UPDATE: For one such case that the court cites, State v. Burk (Wash. 1921), see here.] One possible textual justification for this right, the court concluded, is the Washington Constitution's provision that "[t]he enumeration in this Constitution of certain rights shall not be construed to deny others retained by the people" (an analog to the federal Ninth Amendment).
2. The court also concluded that right to self-defense should also be understood as protected by substantive due process. Though the federal precedent on that question is mixed, the court read the cases as on balance cutting in favor of recognizing such a right. (See this post for more.)
3. The Washington Constitution expressly secures a "right of the individual citizen to bear arms in defense of himself, or the state." The court concluded that this provision and the Second Amendment "are most reasonably read not as creating a right of self-defense but as lending support to the existence of an unenumerated right to self-defense retained by the people or fundamental to due process," though the court also noted that some other courts "have read constitutional guarantees of a right to bear arms as implicitly guaranteeing a right to self-defense."
Though "the State successfully argued in the trial court and argues again on appeal that [the Washington precedents] all dealt with protection of property and do not support a right to personal self-defense against an attacking animal," the court concluded that these three arguments "support an equal if not greater constitutional right to personal self-defense." [UPDATE: Note that the trial court agreed that the defendant could argue that he was justified in shooting the dog, but only under the rubric of the "necessity" defense, not the "self-defense" defense. And the necessity defense in Washington requires the defendant to prove necessity - here, that shooting the dog was necessary to protect himself from injury - by a preponderance of the evidence; the self-defense defense in Washington requires the state to disprove self-defense beyond a reasonable doubt.]
Now on the facts of the case, this particular defendant might well not have been entitled to prevail on a self-defense theory. Indeed, the court concluded that some of the shots that the defendant fired were unjustified even under his own account of the facts; the defendant's conviction for recklessly discharging a firearm was therefore upheld. The court also concluded that a properly instructed jury could convict the defendant even as to the shooting of the dog, if it didn't believe the defendant's version of the facts. But the court held that, if the defendant is retried for shooting the dog, he is "entitled to have the jury instructed on his right to self-defense."