Thomas Feltes, criminologist at the Ruhr University Bochum, wrote: "Without his books, the average reader would be missing something, and certainly also some investigators who, after their publication, will eagerly search for who is quoted, named or otherwise indirectly mentioned in them.

Former Chancellor Gerhard Schröder took legal action against his 2006 book The Germany Clan: The Unscrupulous Network of Politicians, Top Managers and the Judiciary.

The court ruled that Roth had to rewrite a passage in the book in which he linked a trip by Schröder to the United Arab Emirates with his work for Gazprom.

[9] From the summer of 2007, Roth wrote about an alleged Saxony swamp over claims that high-ranking politicians, lawyers, police officers and journalists were members of mafia structures.

[10][11] Roth was heavily criticized by the journalist Reiner Burger, who describes the Saxony swamp as a legend, in a series of articles in the Frankfurter Allgemeine Zeitung.

[14][15] Roth wrote in Schmutzige Demokratie, a 2016 compendium of vignettes, for example that a young Hungarian politician who would later rise to international prominence was the victim of kompromat, because he had accepted a considerable bribe from a Russian organized crime figure through an intermediary twenty years earlier.