LOUISVILLE, Ky. -- A Kentucky National Guard soldier with aspirations of joining a U.S. Army special operations unit wants a federal judge to overturn the military's new regulations concerning soldiers with tattoos.

Staff Sgt. Adam C. Thorogood of Nashville, Tenn., said the tattoos covering his left arm from the elbow to the wrist aren't harmful, but the Army is using the body art against him and stopping him from fulfilling a dream of joining "The Nightstalkers," the 160th Special Operations Aviation Regiment at Fort Campbell, Ky. Thorogood's attorneys said the new rules are preventing their client from seeking appointment as a warrant officer.

Thorogood, 28, sued Thursday in U.S. District Court in Paducah, Ky., seeking to have the new rules declared unconstitutional. He is seeking $100 million in damages.

The regulations went into effect in March cover a variety of appearance-related issues including hair styles, fingernails, glasses and jewelry. The rules ban tattoos below the knee or elbow. Soldiers who already have the ink are grandfathered in. Under the new regulations, any soldier with tattoos is barred from seeking a promotion to warrant officer or commissioning as an officer.

"You've got a soldier who is about as gung ho as you get ... then you've got this regulation you read about on Facebook and you don't have a career," said Robin May, a Kentucky-based attorney who represents Thorogood. "That would be a blow."

May said the new regulations violate a constitutional ban on laws that retroactively change the legal consequences or status of actions that were committed before the enactment of the law. The ban also infringes upon Thorogood's free speech rights, May said.

An Army spokesman did not immediately return a message Thursday. In an online video posted in March, Sgt. Maj. of the Army Raymond F. Chandler III addressed why the changes were made, saying appearance matters and should "be a matter of personal pride" to soldiers.

"The Army is a profession, and one of the ways our leaders and the American public measure our professionalism is by our appearance," Chandler said. "Every soldier has the responsibility to understand and follow these standards. Leaders at all levels also have a responsibility to interpret and enforce these standards, which begins by setting the example."

Tattoos have long been a part of military culture, but as they have become more popular, and more prominently displayed on the body, the various branches have been regulating them to try to maintain a professional look. The Air Force bans tattoos covering more than a quarter of an exposed body part, under regulations revised in 2011. In 2006, the Navy announced that forearm tattoos could be no wider than a hand's breadth.

The Marine Corps has been cracking down on tattoos for years. In 2007, the Corps banned sleeve tattoos and those covering the leg below the knee.

Thorogood spent 10 years on active duty in the Army as a decorated soldier and sniper before switching to the reserves, a move that allowed him to pursue a degree in aerospace at Middle Tennessee State University and pursue certifications in flying planes. Attorney Ken Humphries said Thorogood's goal was to submit an application for an appointment as a warrant officer, who are usually technical leaders and specialists, and become a helicopter pilot.

Thorogood has 11 tattoos, including three on his left arm featuring a three-member sniper team, a second of skulls and the sniper logo of a serpent and spear and an ambigram of the words "Fear Is the Mind Killer." Once the tattoo regulations took effect, body art that Thorogood had before the regulations could get him charged with a military offense if he even applied for the position.

"It disqualifies a candidate for cosmetic reasons," Humphries said.