I have been asked this (perfectly fair) question many times in the past month or so while discussing my new book which features a detailed examination of the 2003-07 NBA betting scandal, and will humor answering it more fully here for others to reference.
As I explain in Gaming the Game, at the onset of the research in March 2008, I planned to attempt interviewing the former NBA referee. In time, however, I discovered how many demonstrably false claims Donaghy has made, and decided against trying to contact him.
“…we’ve never taken the position that Mr. Donaghy has lied to us. But, there is a difference between telling the truth and believing you’re telling the truth and finding out later that a number of allegations don’t hold any water” (emphasis added).
“several sources described him as fairly unpopular with his peers, past and present…From his Philly basketball roots to his peers in the NBA, Donaghy isn’t described with much affection.”