A collection of Treasury documents (T 1/439/156-160) concerning John Dexter, who attempted to inform on smuggling operations on the Isle of Man but had his letters intercepted by smugglers. The file includes a covering letter from the Customs Commissioners, affidavits from two witnesses (Margaret Quirke and Mary Cain) defending the treatment of Dexter's wife during her confinement, and Dexter's own petition seeking employment in the Customs service as recompense for his loss and service to the Crown. The affair illustrates the dangers faced by informers, the dominance of smuggling interests on the island, and the vulnerability of Crown officials.