The "Mafia Expert" (sic) is an investigative journalist and writer, fairly famous in Italy, which for his work has received enough death threats that he will probably have to live under police protection the rest of his life...
Saviano is officially known in Italy to be a writer, way more than a journalist - actually he was completely unknown before his first book "Gomorra", which made him famous, and he admitted not to be "a journalist, (nor a reporter), ... but a writer" (http://www.thedailybeast.com/articles/2015/09/24/mafia-autho...). I would add that in Italy he is pretty known to be a good show-man, even more than a writer.