James takes his revenge on his Albany Stewart relatives on March 21, 1425, on the ninth day of the March Parliament.
Murdoch is arrested, along with his younger son Lord Alexander Stewart.
Immediately afterwards, twenty-six of the principal nobles and barons in Scotland share the same fate.
Albany is at first confined in the castle at St. Andrews and afterwards transferred to Caerlaverock Castle.
His wife Isabella is captured in the family's fortified castle of Doune, their favorite residence, and committed to Tantallon Castle.
The King's rage at Duke Murdoch has its roots in the past.
James's older brother David Stewart, Duke of Rothesay, had died young, in Falkland Castle, while in the care of Murdoch's father, Robert Stewart, Duke of Albany.
Though Albany had been exonerated by Parliament, the suspicion of foul play had remained.
Moreover, neither Duke Robert nor his son Murdoch had greatly exerted themselves in negotiating James's release while in English captivity.
This may well have left James with the suspicion that the Albany Stewarts have personal designs on the throne of Scotland.
At this time, Albany's other son Walter is already in prison.
Only James, Murdoch's youngest son (also known as James the Fat) is able to escape James's vengeance.
He escapes into the Lennox, where he begins to organize a revolt, leading the men of Lennox and Argyll in open rebellion against the crown.
This resort to violence by Albany's youngest son may have been what the king needed to bring a charge of treason against the Albany Stewarts.
Duke Murdoch, his sons Walter and Alexander, and Duncan, Earl of Lennox are in Stirling Castle for their trial on May 18, 1425, at a prorogued parliament in the presence of the King.
An assize of seven earls and fourteen lesser nobles hears the evidence that links the prisoners to the rebellion in the Lennox—in a trial lasting just one day, the four men are found guilty of treason.
The jury that condemns them is composed of twenty-one knights and Peers, including Albany's cousin Walter Stewart, Earl of Atholl, Archibald Douglas, 5th Earl of Douglas, Alexander, Earl of Ross and Lord of the Isles, and Alexander Stewart, Earl of Mar.
Walter is condemned on May 24.
Albany and his son Alexander are tried before the same jury the following day.
All the prisoners are then publicly beheaded on Heading Hill "in front of" Stirling Castle.
Albany is attainted and all of his peerage titles are forfeited.
He is buried at Blackfriars' Church, Stirling.
In the destruction of his close family, the Albany Stewarts, James I is able to secure the substantial rents from the family's three forfeited earldoms of Fife, Menteith and Lennox, a blow from which the Albany Stewarts will never recover.
