Dead Man in Paradise, by James MacKinnon

This true-crime thriller unfolds in the Dominican Republic in the years following the infamous Trujillo regime. For three decades from 1930, President Trujillo had plundered the government coffers and maintained his family in power. His longed-for assassination in 1961 and the subsequent US occupation, however, did little to stop the corruption or brutality. In 1965 a Canadian priest, Father Arthur MacKinnon, was shot dead, apparently because he refused to stop at a check-point. His death has remained unsolved.

James MacKinnon, a Canadian journalist and nephew of the deceased priest, sets out to investigate that murder 40 years ago. Who killed his uncle, and why? MacKinnon remains steady on the case, checking files and tailing suspects in an attempt to understand a death that has long troubled his family. He concludes that Father Arthur was the victim of local business interests and that his assassination was political. The priest's involvement in rural co-operatives and his attempts to redistribute land had riled former pro-Trujillo strong men and put his life at risk. MacKinnon was a leftist Catholic missionary whose antipathy to US interests in the Republic was well-known; the authorities were only too willing to eliminate him.

As well as a whodunit, Dead Man in Paradise provides a geography lesson of sorts. The Dominican Republic must be the only island today, apart from Cyprus, divided into two independent states, each moreover speaking a different language: in Haiti, French; Spanish in the DR. Trujillo's contempt for the "backward and dirty" Haitians is one of the themes of this book. To earn a crust, Haitians have traditionally worked for wretchedly low wages in the Dominican sugar industry. In 1937, during a racialist purge of the sugar plantations, Trujillo's National Guard massacred some 25,000 Haitian cane-cutters. The atrocity has echoed down the generations in this part of the Caribbean; but, as MacKinnon establishes, Trujillo tried to conceal the extent of the bloodbath, just as he tried to hide the truth of his sexual depredations, amply documented by Mario Vargas Llosa in his novel The Feast of the Goat.

MacKinnon describes the machista culture and indolence of the modern Dominican Republic, as former Trujillistas, policemen and archivists hamper his research. Bizarrely, Father Arthur's body had been found plugged with bullets alongside the corpses of two policemen. It would seem that the police had been sent to execute the priest, and were afterwards eliminated: a classic "Trujillonian" cover-up. Father Arthur was 33 at the time.

MacKinnon displays a terrier-like determination, and vividly describes the Klondike sleaze of such towns as Jimani and Dajabon. The author himself is not a Catholic, yet he remains sympathetic to his uncle's Jesuitical insistence on "social justice" for the poor. If the book has a fault, it lies in passages of overwrought prose. "Clouds boil in the sky," we are told, "and press down like an avenging hand." MacKinnon has a weakness, too, for highfalutin' words like "immutable" and "inexorable". However, these are hiccups in a superb work of reportage, which blends documentary sources with imaginative conjecture to create a memorably good thriller.

Ian Thomson, author of 'Bonjour Blanc: a journey through Haiti' (Vintage), is working on a book about Jamaica