He was wrongfully accused and hanged as an accessory to the Appin Murder, the assassination of Colin Roy Campbell.

[4] Colin Roy Campbell, a government factor of estates forfeited by pro-Jacobite clans following the Rising of 1745, was shot in the back on 14 May 1752.

[4] Although the trial showed that James was not directly involved in the assassination (he had a solid alibi), he was found guilty "in airts and pairts" (as an accessory; an aider and abetter).

Before mounting the scaffold, he sang the 35th Psalm in Scottish Gaelic: "False witnesses rose; to my charge things I not knew they laid.

James's corpse was left hanging at the south end of the Ballachulish Ferry for eighteen months as a warning to other clans with rebellious intentions.