During the few months that remained to him of life he embarked upon a veritable Odyssey:  he scoured Scotland from the Border to St. Andrews, and finally contrived a journey oversea to Ireland, where he made the name of Daniel O’Brien a terror to well-doers.  Insolent and careless, he lurched from prison to prison; now it was Armagh that held him, now Downpatrick, until at last he was thrust on a general charge of vagabondage and ill-company into Kilmainham, which has since harboured many a less valiant adventurer than David Haggart.  Here the culminating disgrace overtook him:  he was detected in the prison yard by his ancient enemy, John Richardson, of Dumfries, who dragged him back to Scotland heavily shackled and charged with murder.  So nimble had he proved himself in extrication, that his captors secured him with pitiless severity; round his waist he carried an iron belt, whereto were padlocked the chains, clanking at his wrists and ankles.  Thus tortured and helpless, he was fed ‘like a sucking turkey in Bedlam’; but his sorrows vanished, and his dying courage revived at sight of the torchlight procession, which set forth from Dumfries to greet his return.

His coach was hustled by a mob, thousands strong, eager to catch sight of Haggart the Murderer, and though the spot where he slew Morrin was like fire beneath his passing feet, he carried to his cell a heart and a brain aflame with gratified vanity.  His guilt being patent, reprieve was as hopeless as acquittal, and after the assured condemnation he spent his last few days with what profit he might in religious and literary exercises.  He composed a memoir, which is a model of its kind; so diligently did he make his soul, that he could appear on the scaffold in a chastened spirit of prayerful gratitude; and, being an eminent scoundrel, he seemed a proper subject for the ministrations of Mr. George Combe.  ‘That is the one thing I did not know before,’ he confessed with an engaging modesty, when his bumps were squeezed, and yet he was more than a match for the amiable phrenologist, whose ignorance of mankind persuaded him to believe that an illiterate felon could know himself and analyse his character.

His character escaped his critics as it escaped himself.  Time was when George Borrow, that other picaroon, surprised the youthful David, thinking of Willie Wallace upon the Castle Rock, and Lavengro’s romantic memory transformed the raw-boned pickpocket into a monumental hero, who lacked nothing save a vast theatre to produce a vast effect.  He was a Tamerlane, robbed of his opportunity; a valiant warrior, who looked in vain for a battlefield; a marauder who climbed the scaffold not for the magnitude, but for the littleness of his sins.  Thus Borrow, in complete misunderstanding of the rascal’s qualities.