(New York Times) The pharmaceutical giant Pfizer announced on Friday that it has imposed sweeping controls on the distribution of its products to ensure that none are used in lethal injections, a step that closes off the last remaining open-market source of drugs used in executions.

More than 20 American and European drug companies have already adopted such restrictions, citing either moral or business reasons. Nonetheless, the decision from one of the world’s leading pharmaceutical manufacturers is seen as a milestone.

“With Pfizer’s announcement, all F.D.A.-approved manufacturers of any potential execution drug have now blocked their sale for this purpose,” said Maya Foa, who tracks drug companies for Reprieve, a London-based human rights advocacy group. “Executing states must now go underground if they want to get hold of medicines for use in lethal injection.”

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