What to Know U.S. Rep. Duncan Hunter served in Iraq as a U.S. Marine in 2003.

A federal grand jury indictment depicts the Hunters as binge spenders who misused campaign funds for over eight years.

Hunter has defended some of the spending, saying trips paid for with campaign funds were for fundraising.

The U.S. Marine Corps is demanding U.S. Rep. Duncan Hunter stop using its trademark logo and phrase in his campaign materials.

The U.S. Marine Corps sent the congressman a cease-and-desist letter.

The U.S. Marine emblem appears at the top corner of the campaign mailer with the slogan "No better friend. No worse enemy." Both are registered trademarks.

As NBC 7 reported Tuesday, critics claim Hunter’s latest campaign mailer is Islamophobic. The envelope and literature target Democratic challenger, Ammar Campa Najjar and two members of the U.S. Congress.

“It is personally disappointing to Congressman Hunter that he is now being told that he cannot use this motto or image that thousands of Marines like Congressman Hunter, who went to war under this banner, have used for tattoos, coins, and multiple other items of personal sentiment. It is as much a part of them as it is the Marine Corps,” a Hunter spokesperson told NBC 7.

A military spokesperson said this in response to our request for a comment: "The Eagle, Globe, and Anchor is a trademark of the Marine Corps protected by Federal law...The seal and emblem should not be used in conjunction with any political activities. The Marine Corps has taken appropriate action to address the referenced mailers."

The Republican congressman has been charged with 60 criminal counts including misusing campaign funds for years and filing false records. He is accused of using more than $250,000 in campaign contributions to pay for family trips to Italy and other locations, golf outings, dental work and more.

His wife, Margaret Hunter, has entered a guilty plea in the case.

The congressman, who has said the federal charges are politically motivated, is scheduled to go to trial in September.