A major in the Marine Corps is scheduled Friday in federal court to fight an attempt to boot him from the service because he sent a classified document over his personal Yahoo account in an effort, he says, to save the lives of fellow Marines.

Major Jason Brezler says he sent the classified document, about an allegedly corrupt Afghan police chief, on the unsecured account that was available. However, if his email had been acted upon, it might have prevented the killing of three Marines in Afghanistan in 2012, including that of Lance Cpl. Gregory Buckley Jr. of Oceanside, according to court papers and his attorneys.

The 2013 decision of a Marine board of inquiry to expel Brezler from the Marine Corps reserves, albeit with an honorable discharge, is on hold pending the outcome of the case before U.S. District Judge Joseph Bianco in Central Islip. Brezler, of Brooklyn, is a FDNY firefighter who graduated from the Naval Academy in Annapolis, Maryland, and has served four tours of duty in Afghanistan.

Brezler and his attorneys have maintained that an initial investigation determined that he should get no punishment. But when Rep. Peter King (R-Seaford), who represents Buckley’s area, began asking the Marines why the inquiry board had been convened, Brezler’s expulsion was ordered. This is an attempt to cover up a Marine commander’s failure to act on the confidential report, they say.

King, in an interview earlier this week, called Brezler’s treatment “a travesty of justice.”

“Here you have Marines killed, and the only one who did the right thing — he’s being punished,” King said.

advertisement | advertise on newsday

Nicholas Biase, a spokesman for the U.S. Attorney’s Office for the Southern District, which is defending the Marine Corps and the Navy in the case, declined to comment. Though the case is being heard in the Eastern District on Long Island, Southern District prosecutors are defending the government to avoid a conflict of interest because the Eastern District has a separate criminal investigation into the deaths of the three Marines.

Government attorneys say in court papers that Brezler received a fair hearing, and the decision was reviewed and approved by Marine and Navy officials. Government attorneys also noted it is highly unusual for federal courts to intercede in military decisions.

But Brezler’s attorneys, Michael Bowe and Kevin Carroll, have said that the Brezler hearing was filled with procedural errors and the retaliatory motive behind it was clear, so civilian federal courts should intercede in this instance.

The classified email Brezler sent involved the background of an Afghan police officer named Sarwar Jan. Brezler had been instrumental in 2010 in expelling Jan from a Marine base when he was in Afghanistan because of his corruption and his keeping young boys as sex slaves, the court papers said.

When Brezler left Afghanistan to attend graduate classes in Oklahoma in 2012, a fellow officer emailed him to say that Jan had returned to work at a Marine base and asked Brezler if he had any information on Jan. The confidential file on Sarwar Jan was what Brezler emailed back. Several weeks later a 15-year-old boy who accompanied the police chief to the base took a rifle and shot Buckley and the two other Marines to death, according to court files and defense attorneys.

Brezler’s attorney Bowe only would say earlier in the week: “We have presented compelling evidence and are looking forward to having the court pass on the propriety of the Marine Corps actions.”

The family of Buckley, the Oceanside Marine, has filed a separate civil suit in the Eastern District asking the courts to order the Marines to turn over all records of the case, which they say they are entitled to as relatives of a deceased service member. That case is pending.

George Buckley Sr., the father of the dead Marine, could not immediately be reached for comment.