Glug,
In most Australian states and Wisconsin there is a defense of “provocation” to a charge of murder.
If something has occurred which causes an offender to lose emotional control then murder is reduced to manslaughter. The offender is said not to have the necessary Mens Rea or intent for a murder conviction.
Firing a semi automatic weapon at an armed adversary probably satisfies this defense. Adrenalin and fear would have been pumping as the subsequent shots were fired.
Bacci