Double murder is the act of murdering two people. This can be punished by back-to-back life sentences in the US. It is possible but rare for a double-murder charge to be enforced in cases of homicide in which a pregnant woman is murdered, thereby killing her unborn fetus, such as in the Laci Peterson case. Even though it is not necessarily correct, the term is often attached to incidents involving higher numbers of people such as if three or four people were to be murdered.
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