In 1852, when the Original Secession Synod, of which he was Moderator, decided, by 32 votes to 31, to unite with the Free Church, Thurso congregation at a regular meeting agreed by a majority of one to do the same. The question of legal rights now passed into the Court of Session, and hence arose the Thurso Case, in which it was declared that the property belonged, according to the title-deeds, to the minority, who stood by the binding obligation of the Covenants. Burn and his adherents now vacated the old building, and formed the West Free Church, Thurso. The party who kept by the Original Secession Synod had inevitably to face decline, and in 1884 their membership was down to 50, and the stipend, though liberal for their numbers, was only, £94 with a manse. Burn died, 29 April 1882.