A forthcoming paper by a University of Pennsylvania professor and Cornell University graduate student says that, during the 13 seasons from 1991-92 through 2003-04, white NBA referees called fouls at a greater rate against black players than against white players.
The study also found a bias in which black officials called fouls more frequently against white players, though that tendency was smaller.
NBA Commissioner David Stern said the league saw a draft copy of the paper late last year and was moved to conduct its own study this March using its own database of foul calls, which specifies which official called which foul.
Three independent experts asked by The Times to examine the paper and materials released by the NBA said they considered the professor/student argument far more sound.
