Senator Charles E. Grassley, one of Capitol Hill’s most vocal nonprofit watchdogs, took aim Tuesday at private colleges that provide their leaders with extra cash to cover taxes on bonuses and other financial perks, writes The Chronicle of Higher Education.

The Iowa Republican issued a statement to the newspaper in response to its latest survey of presidential pay at private institutions, which showed that half of the 50 best-paid campus leaders in 2010 received the tax assistance.

“This kind of approach to spending makes you wonder if federal aid and federal tax exemption are doing everything possible to help make college more affordable as intended or if they are enabling better perks for college presidents,” Mr. Grassley said.