Maroney maintains he did nothing wrong Oct. 28 when he used pepper spray on the patient, who has a history of mental illness, ,before striking the man four times with his nightstick.
A security camera captured the incident on video. The tape has been turned over to the FBI for review to determine whether criminal charges are warranted.
An initial review by Maroney's commander, then-VA Police Chief Gerard Ousley, found no wrongdoing. But an administrative review board then examined the video and determined that Maroney had used excessive force.
After the incident, the 20-officer department was audited; and Ousley was reassigned.
Maroney's attorney, Jason Wunsch of Lillington, said Thursday that his client has yet to be interviewed by the FBI.
The fired officer, who served in the Army as a military police officer before joining the VA's police force seven years ago, plans to appeal his dismissal.
"The legal fight has just begun," Wunsch said. "He's very upset. Obviously, he does not agree with the decision."
Citing the ongoing criminal investigation, officials at the Durham VA denied a Freedom of Information Act request filed in February for the hospital's internal administrative report of the incident. The News & Observer appealed that denial March 10, but as of Thursday no decision about whether to release the document had been made in Washington.
In an interview last month, Maroney said the incident began when he and his supervisor were called and told a patient was causing a disturbance in one of the Durham center's clinics. Maroney and another officer were escorting the patient to an isolation room when Maroney says the man hit him in the face.
Maroney pepper-sprayed the patient. When that failed to subdue him, Maroney said he hit the man with a baton on his forearm and hand before pushing him to the ground and handcuffing him.
Maroney said that he was not trained to consider a patient's age or mental state when using pepper spray or his baton.
The VA's training manual says that officers are permitted to use only that amount of force "necessary and reasonable to overcome the resistance being offered ... without using excessive force." The policy goes on to say that when using their batons, officers "must be trained to use it properly in order to obtain the desired results when used, and at the same time avoid bringing criticism upon themselves or the Department of Veterans Affairs."