(This post has been updated)

Republican lawmakers kept up their criticism Monday of Gov. Mark Dayton's salary hikes to state agency commissioners, as the governor responded with a letter to top legislative leaders spelling out the legal justification for the pay boosts, and a detailed argument in defense of them.

Dayton also released a March 2013 letter from a bipartisan council of state lawmakers and others that recommended across-the-board salary hikes for Minnesota judges, constitutional officers, legislators and state agency heads.

Months later the DFL-controlled Legislature responded with a bill that let the governor raise the pay of his cabinet commissioners without further legislative approval. Dayton responded with raises that totaled more than $800,000 a year, and gave raises as much as $35,000 a year for some commissioners.

At a meeting of the House Ways and Means Committee, Republican lawmakers amended a stopgap spending bill to cut a total of about $40,000 in one-time funds for the departments of Health, Human Services and Natural Resources. Republicans said those funds should be subtracted from the salary hikes for those three commissioners.

Another House committee may further review the raises later this week.

"Reasonable people can disagree about what government officials should be paid," Dayton said. But he said there should be no debate about the legality of his actions.

"My administration followed the 2013 statute very carefully," Dayton wrote.

Defending his decision, Dayton noted that mid-level managers at many Minnesota companies earn more than his commissioners, who post-raise are earning between $140,000 and $155,000 a year. He also pointed out that even after the raise, the state education commissioner is still earning about 80 percent of the yearly salary of superintendents at a number of larger Minnesota school districts.

"Not one has ever asked me for a raise," Dayton wrote of his commissioners. "But they, like other working Minnesotans, deserve compensation that is commensurate with their responsibilities."

Dayton ended the letter by noting he also considers state legislators "woefully underpaid." Rank-and-file lawmakers earn $31,140 a year and legislative leaders make $43,596.

"Those low salaries are mired in the outdated mythology of a part-time legislature," Dayton wrote. "I am ready to do whatever I can to help bring legislative salaries up to more appropriate levels through significant, one-time adjustments, as I have just made to the executive branch."