US Supreme Court backs use of contentious execution drug

The US Supreme Court has upheld the use of a contentious drug used in executions, saying it does not violate a ban on cruel and unusual punishment.
The ruling is a setback to opponents of the death penalty, who say midazolam is not suitable for lethal injections.
The drug raised concerns after it was used in executions in three US states in 2014 that took longer than usual.
Executions have been delayed recently in the US amid problems buying drugs as many firms have refused to sell them.