The habit of comparing senior public sector workers' pay to that of the prime minister is an "irrational trend" that could damage the ability to recruit top staff, according to a key report on public sector salaries.
Will Hutton's comments, in the first installment of a Government-commissioned fair pay review, come after education secretary Michael Gove asked the School Teachers' Review Body to consider limiting headteachers' pay to the #163;142,000 wage of David Cameron.
Mr Hutton has recommended that top pay in the public sector should not be more than 20 times that of the lowest-paid worker in an organisation, following wage inflation in recent years.
"Government responses have not been sufficient to quell public outrage," he wrote. "There is an irrational trend to compare the salaries of all public servants with that of the prime minister.
"The prime minister's formal salary considerably underestimates the value of his full benefits package and reflects a heavy 'discount' intrinsic to the nature of a political career.
"With some 9,000 people earning more than this across the public sector, widespread use of this benchmark would risk damaging a wide range of organisations' ability to recruit and retain talented individuals."
While Mr Hutton does not mention schools specifically, his comments follow criticism of the potential capping of headteachers' salaries voiced over the past few months.
Brian Lightman, general secretary of the Association of School and College Leaders, has said he is not against a pay cap, but that using Cameron's salary as a measure is arbitrary.
Anne Wright, chair of the School Teachers' Review Body, has already warned Michael Gove that the cap might actually lead to pay inflation, as heads see it as a goal.
A handful of highly paid heads have been among dozens of public servants criticised for their salaries in recent months.