(CNN) -- Authorities in Colorado have filed charges against the parents in last month's notorious "balloon boy" case, and the pair's lawyers say the two are expected to plead guilty on Friday.

The Larimer County district attorney's office Thursday said Richard Heene has been charged with one count of attempting to influence a public servant, a felony, and Mayumi Heene has been charged with one count of false reporting to authorities, a misdemeanor.

Richard Heene turned himself in Thursday afternoon and was released on a $5,000 personal recognizance bond, the Latimer County Sheriff's Office said. Mayumi Heene did not appear with him.

The Heenes will appear Friday in Larimer County Court, where they are expected to plead guilty, their attorneys said.

The penalty range for the felony is two to six years in prison with a fine of $2,000 to $500,000. The range for the misdemeanor would be six months in jail with a fine of $50 to $750, the district attorney's office statement said.

The Heenes' attorneys said prosecutors have agreed to a sentence of probation with the possibility of up to 90 days in jail for Richard Heene and up to 60 days in jail for his wife.

The threat of deportation for Mayumi Heene was a factor in the plea deal negotiation, the attorney's statement said.

"Mayumi Heene is a citizen of Japan. As such, any felony conviction or certain misdemeanors would result in her deportation, even though her husband and children are Americans," the statement said.

"It is supremely ironic that law enforcement has expressed such grave concern over the welfare of the children, but it was ultimately the threat of taking the children's mother from the family and deporting her to Japan which fueled this deal."

Prosecutors in the case could not be immediately reached for comment.

On October 15, a large silver balloon came loose from moorings in the Heenes' yard and floated over Colorado. Mayumi Heene called 911 and said the couple's 6-year-old son Falcon was inside the craft.

Millions of people across the country watched the saga on television for nearly two hours as military aircraft tracked the balloon in the air and rescuers chased it on the ground.

Mayumi Heene later admitted the whole thing was a hoax and that Falcon was safe in their home the whole time, authorities said.

Watch the moment the hoax was revealed

Court documents released last month said the couple hatched the plan about two weeks before the incident and "instructed their three children to lie to authorities as well as the media regarding this hoax."

Their motive? To "make the Heene family more marketable for future media interests," the documents said.