The number of homosexually inclined priests active in America is not an unknown factor, the Linacre study [After Asceticism: Sex, Prayer and Deviant Priests] noted. If 81 percent of American Catholic priests are homosexually inclined, then the ratio of male-to-male abuse is unremarkable; the statistics would suggest that homosexual and heterosexual men are equally likely to engage in sexual abuse. If the proportion of homosexual priests is very low, on the other hand, then the disproportionate number of male sex-abuse victims is all the more noteworthy. If only 2 percent of priests are homosexual, the Linacre Center concluded, [then] those few homosexuals are more than 120 times as likely as heterosexuals to be guilty of abuse.
--Philip F. Lawler,The Faithful Departed: The Collapse of Boston's Catholic Culture (2008), p. 225
On that 81% figure, see, for example, More than 80 percent of victims since 1950 were male, report says, by Kevin Cullen, Boston Globe, February 28, 2004. A recent Los Angeles Times editorial on the Pope's new edict on the priesthood said of the percentage of homosexual priests that "estimates range from 25% to 50%". This all leaves out of consideration the percentage of abusers among priests compared to that percentage in the general population, and the change in the percentage among priests over time.