Which of the following is NOT a requirement for a second-degree murder charge?

Second-degree murder in Missouri involves a few specific requirements, focusing primarily on the intent and circumstances surrounding the act of causing death. One key element is that the perpetrator must knowingly cause the death of another person. This involves a level of awareness regarding the actions and the potential consequences of those actions.

Additionally, intent to cause serious injury that results in death can also lead to a second-degree murder charge, as it indicates a reckless disregard for human life. Moreover, the felony murder rule can apply, where a death occurs during the commission of a dangerous felony, thus constituting murder due to the underlying felony act.

However, the requirement that is not necessary for a second-degree murder charge is the intentional planning of the murder for a long time. This element more closely aligns with first-degree murder, which necessitates premeditation and deliberation. Second-degree murder does not require this level of planning, as it may arise from spontaneous actions or decisions rather than a calculated scheme. Hence, the absence of long-term planning distinctly separates second-degree murder from more severe charges, making it clear why this option does not fit the criteria for a second-degree murder charge.