Washington Pattern Jury Instructions–Criminal (W.P.I.C.)
Part IV. Defenses Chapter 15. Excusable Homicide
WA W.P.I.C. 15.01 Excusable Homicide—Definition
It is a defense to a charge of [murder][manslaughter] that the homicide was excusable as defined in this instruction.
Homicide is excusable when committed by accident or misfortune in doing any lawful act by lawful means, without criminal negligence, or without any unlawful intent.
The State has the burden of proving the absence of excuse beyond a reasonable doubt. If you find that the State has not proved the absence of this defense beyond a reasonable doubt, it will be your duty to return a verdict of not guilty.