A well-known criminal defense attorney faces felony charges of trying to persuade witnesses to lie to authorities and possessing one or more stolen guns, as well as a charge of domestic assault.

Anthony J. Sineni III, 52, of Standish was arrested by Cumberland County sheriff’s deputies Saturday night at a home on Shore Road in Cape Elizabeth.

It’s not clear what led to the charges against Sineni because the affidavits supporting the arrest warrant have been sealed by the court at the request of the Maine Attorney General’s Office. Prosecutors say the files were sealed to “ensure the ability to pick a jury if the matter goes to trial.”

It is unusual for the conduct underlying an arrest to be kept secret, other Maine lawyers said.

“I have never seen a domestic violence non-homicide (affidavit) continue to be impounded after an arrest,” said J.P. DeGrinney, a Portland attorney. “I’ve been practicing criminal law since 1994 and I’ve never seen it.” DeGrinney said he knew nothing about the case against Sineni.

The Cumberland County District Attorney’s Office requested that the Attorney General’s Office prosecute the case to avoid any appearance of conflict, because Sineni has many clients with cases pending in the county court system.

The case may be connected to a protection from abuse order taken out Friday against Sineni by the mother of his children in which she says he threatened to kill her. It is the latest in a series of protection orders between Sineni and his sometime partner, Winona Hichborn, 34, who lives in Windham. In her request for a protection order, Hichborn said Sineni has assaulted her on multiple occasions.

“I am very fearful because Tony is spiraling out of control. With his abusive behavior, erratic tendencies and access to guns, I don’t trust him having my sons,” she wrote Friday.

Hichborn said she and Sineni have been together on and off for many years and that there has been an extensive history of domestic violence. Sineni has no criminal history, according to the State Bureau of Identification.

Hichborn’s request includes a description of recent assaults and said that he wanted her to tell police that his guns belonged to her so that he wouldn’t get in trouble.

She also said Sineni has told the three children they have, one of whom is hers from a previous relationship, not to speak to police unless he is there.

The only other protection order involving the couple that was available in the Cumberland County Courthouse in Portland was from 2009, and includes a statement from Sineni accusing Hichborn of having substance abuse and mental health issues, such that he felt their children were not safe with her. Sineni’s protection order recounts multiple instances where he said Hichborn was intoxicated.

John Pelletier, executive director of the Maine Commission on Indigent Legal Services, said Sineni is on the state’s list to accept court-appointed cases for criminal defendants who cannot afford their own lawyers.

“I think all I can say at this point is we’re aware of it and getting information at this time to decide what the best course may be,” Pelletier said.

Jacqueline Rogers, executive director of the Maine Board of Overseers of the Bar, said Maine Bar rules allow the bar’s counsel to pursue disciplinary action in such cases only if the attorney is convicted of a crime. “Ultimately, everyone is innocent until proven guilty,” Rogers said. “But will we monitor it? Yes.”

Sineni is free on $10,000 bail pending a court appearance.