Ernest Johnson's legal team argued he had an intellectual disability
A man from Missouri in the US has been executed for murdering 3 people convenience employees in 1994.
The 61 year-old was injected with a lethal dose of pentobarbital yesterday evening.
This is despite pleas for Mr. Johnson's life to be spared.
His legal team argued he had an intellectual disability, caused by foetal alcohol syndrome, after his mother drank heavily during pregnancy.
Campaign groups had joined the call for a stay of execution - as had a representative of Pope Francis.

Nigel Farage To Resign As MP And Run In By-Election
MEPs Meeting This Morning To Discuss Ireland's EU Presidency
Member States Responsible For Suspending EU Trade Agreement With Israel - Von Der Leyen
€4.1BN Fine Upheld Against Google For Anti-Competitive Practices
"Massive" Russian Strikes In Kyiv Overnight Kills 13 People
Three Irish People Dead And Another Injured After Road Crash In Spain
Possibility Of Over 10,000 Fatalities As Venezuela Declares State Of Emergency After Two Large Earthquakes