New York (CNN) -- The nurses involved in a maternity ward scuffle with Douglas Kennedy should be investigated and disciplined, Kennedy's lawyers say.
Kennedy, Robert F. Kennedy's son, was arrested and faces misdemeanor charges over the melee at a New York hospital last month in which he knocked down a nurse while he was holding his newborn son.
"The only issue is the aggressive and unprofessional conduct of two nurses," attorney Robert Gottlieb said in a letter sent this week to the hospital.
Gottlieb said the Kennedys have asked that a "thorough investigation be undertaken immediately of the nurses involved in this disgraceful incident and that appropriate disciplinary action taken against them."
Kennedy was arraigned last week on harassment and child endangerment charges, attorneys for both sides have said.
Kennedy -- a Fox News contributor -- was trying to take his newborn son for a walk "to get fresh air" outside Northern Westchester Hospital in Mount Kisco on January 7 when two nurses intervened to prevent him from leaving, they said.
Kennedy, who was accompanied by a hospital doctor, allegedly twisted the arm of one nurse to move her away from a door and kicked another after she approached him, according to Elliot Taub, the attorney for both nurses.
The doctor who accompanied Kennedy, Timothy Haydock, who is a longtime family friend, said the nurses had initially agreed to let Kennedy take the baby outside.
"The nurses were the only aggressors," Haydock said in a statement delivered by Kennedy's attorney.
But Taub said neither nurse recognized Kennedy as the child's father and intended to protect the baby, who apparently had not been discharged. They were trying to enforce hospital rules, Taub said.
Northern Westchester Hospital issued a statement Monday in support of the nurses.
"At Northern Westchester Hospital, patient safety is our priority and we completely support the actions of our nursing staff in this case as they were clearly acting out of concern for the safety of a newborn baby."
Kennedy has denied the allegations, saying that "the nurse had no right to grab our child out of his father's arms."
The late Robert F. Kennedy was the younger brother of slain President John F. Kennedy and had served as U.S. attorney general and U.S. senator. He was assassinated in 1968 while campaigning for the Democratic presidential nomination.
CNN's Susan Candiotti contributed to this report.