Benson, who noted at sentencing that numerous people had written him suggesting sentences, ultimately chose a two-year term.
The judge a one-time Hatch chief of staff who rose to U.S. attorney and the federal bench with the senator's help did not return a call seeking comment Monday.
Hatch, through spokeswoman Heather Barney, strongly denied recommending a sentence.
Hatch "said he doesn't talk to judges unless their cases are already decided," Barney said. "Pat Shea is making false allegations."
It's not illegal for a senator to contact a judge about potential criminal sentences, Shea said, but it does raise professional conduct and ethical questions for a judge such as Benson and a lawyer such as Hatch.
The Senate Ethics Committee also advises senators to refrain from intervening in legal cases not involving them.
DeChristopher's case, stemming from his bogus bids in protest of leasing Utah lands to energy companies at the end of the Bush administration, generated a second wave of protests at his winter trial and July sentencing. Climate activists said his civil disobedience was necessary to prevent damage from fossil-fuel burning, while government prosecutors argued only prison time would uphold the rule of law.
Shea lost to Hatch in the 1994 Senate race and went on to become President Bill Clinton's national Bureau of Land Management director.