Second degree murder, penalty.
565.021. 1. A person commits the crime of murder in the second degree if he:
(1) Knowingly causes the death of another person or, with the purpose of causing serious physical injury to another person, causes the death of another person; or
(2) Commits or attempts to commit any felony, and, in the perpetration or the attempted perpetration of such felony or in the flight from the perpetration or attempted perpetration of such felony, another person is killed as a result of the perpetration or attempted perpetration of such felony or immediate flight from the perpetration of such felony or attempted perpetration of such felony.
2. Murder in the second degree is a class A felony, and the punishment for second degree murder shall be in addition to the punishment for commission of a related felony or attempted felony, other than murder or manslaughter.
3. Notwithstanding section 556.046 and section 565.025, in any charge of murder in the second degree, the jury shall be instructed on, or, in a jury-waived trial, the judge shall consider, any and all of the subdivisions in subsection 1 of this section which are supported by the evidence and requested by one of the parties or the court.
They might even go for second degree if the store ‘strong arm’ robbery or subsequent police beating/ gun discharge is a felony:
MISSOURI STATUTES AND CODES
565.021. Second degree murder, penalty.
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Second degree murder, penalty.
565.021. 1. A person commits the crime of murder in thesecond degree if he:
(1) Knowingly causes the death of another person or, withthe purpose of causing serious physical injury to another person,causes the death of another person; or
(2) Commits or attempts to commit any felony, and, in theperpetration or the attempted perpetration of such felony or inthe flight from the perpetration or attempted perpetration ofsuch felony, another person is killed as a result of theperpetration or attempted perpetration of such felony orimmediate flight from the perpetration of such felony orattempted perpetration of such felony.
2. Murder in the second degree is a class A felony, and thepunishment for second degree murder shall be in addition to thepunishment for commission of a related felony or attemptedfelony, other than murder or manslaughter.
3. Notwithstanding section 556.046, RSMo, and section565.025, in any charge of murder in the second degree, the juryshall be instructed on, or, in a jury-waived trial, the judgeshall consider, any and all of the subdivisions in subsection 1of this section which are supported by the evidence and requestedby one of the parties or the court.
- See more at: http://statutes.laws.com/missouri/t38/c565/565_021#sthash.TgRWVzQg.dpuf