More on constitutional challenges to lethal injection

With thanks to How Appealing for the tip, I see the AP has this informative story about the recent Supreme Court split over whether to grant a stay to a Missouri death row defendant who challenged the state's lethal injection protocol.  I detailed the SCOTUS split in this post which queried whether four Justices ready to grant cert. on the constitutionality of lethal injection protocols, and background on legal challenges to lethal injection can be found in this earlier post which discusses a constitutional challenge to lethal injection unfolding in a Kentucky case.