Isa was convicted and sentenced to death, along with her husband, in the stabbing death of their 16-year-old daughter Palestina Isa. On direct appeal, the Missouri Supreme Court overturned her death sentence because of errors in the penalty phase instruction on aggravating circumstances.

Improper Penalty Phase Instruction on Accessory Liability: First, the instruction contained typos and errors that rendered it “confusing, ambiguous or equivocal, even nonsensical.” 850 S.W.2d at 902. The Court held that “[p]rejudice results because the jury is not given clear guidance. Its deliberations become unchannelled and, therefore, inherently suspect.” Id

Second, the penalty phase instruction contained language from the guilt phase instruction relating to a defendant’s responsibility for the conduct of another. As a result, the instruction “invite[d] the jury to assess Isa’s punishment based on the conduct of her husband” instead of her “own character, record and individual Mindset.” Id. “Although it is permissible to find a person guilty of murder for acts done in concert with another, it is never permissible to sentence a person to death for acts of another.” Id. at 902-903 (citing Lockett v. Ohio, 438 U.S. 586 (1978)).