Walter LaGrand, 37, was convicted of stabbing to death a bank guard in 1982 during an attempted robbery. His younger brother, Karl, was executed for the same crime last week.
Walter LaGrand had exercised his legal right in Arizona to choose death by gassing, rather than lethal injection, in the hope that courts would rule the method "cruel and unusual punishment", and so illegal.
A federal judge upheld that view less than an hour before LaGrand's scheduled time of execution, but subsequent legal appeals permitted the execution to go ahead.
The case had caused diplomatic friction with Germany, which objected that it had not been notified of the two men's plight, although they both had German citizenship.Reuse content