On 12 July 2008, Behan was questioned by the Carabinieri (Italian military police) in connection with the murder of a 72-year-old woman, Silvana Abate Francescatti, at her home on Monte Amiata, Arcidosso, in Grosseto, Tuscany, Italy. The woman was found on 11 July with 13 stab wounds, including a fatal throat wound, but was believed to have died the previous day. Behan, who had been resident in Arcidosso for part of the year since 2006, was arrested after seeking treatment twice at a hospital near Arcidosso for a cut on his thigh. In an interview with The Irish Times, he claimed he had first gone to the hospital on 10 July after cutting himself in the thigh while unpacking furniture and other objects delivered from the USA. However, hospital staff had mistakenly decided he had been acting suspiciously due to his poor spoken Italian, and the fact that he had expressed annoyance at how the hospital was managed and its bad signage.
In November 2008, Behan was cleared of the crime and allowed full use of his home after a chef named Aldo Staiani was identified as the murderer from DNA retrieved from under Mrs. Abate's fingernails. Behan said, "I don't hold any animosity. It's done now, there is no point in bearing any grudges. I am just glad somebody has finally been caught for this brutal killing."