/ Updated 
By Frances Kai-Hwa Wang

Capt. Simratpal Singh, a decorated Sikh-American soldier who has been seeking permission to serve in the U.S. military with his articles of faith intact, filed a federal lawsuit against the U.S. Department of Defense Monday in response to additional non-standard testing being required of him.

“Capt. Singh seeks a religious accommodation for his Sikh articles of faith so that he can continue serving on the same footing as all other soldiers,” Harsimran Kaur, legal director of The Sikh Coalition, told NBC News. “Singling out a Sikh officer to submit to a battery of tests – that aren’t given to the thousands of others soldiers with similar medical and religious accommodations – is discriminatory, un-American and unconstitutional."

Singh — who is being represented by The Sikh Coalition, The Becket Fund for Religious Liberty, and the law firm of McDermott Will & Emery — has been serving in the U.S. Army for over 10 years with his hair cut short and his beard shorn. He is now seeking permanent religious accommodation so that he can both serve his country and practice his faith at the same time.

Singh was granted a temporary 30-day accommodation to serve with his turban and beard intact on Dec. 9, 2015. The exception was extended until March 31, 2016, and on Feb. 26, Singh was ordered to complete additional non-standard testing on March 1 to remain in the military, according to his representatives.

"Captain Singh upholds the finest traditions of our military,” Eric Baxter, senior counsel at The Becket Fund for Religious Liberty, told NBC News. “He’s a West Point graduate, Army Ranger, Bronze Star Recipient. He knows he is subject to the same standards as everyone else. Just this morning, he underwent a previously scheduled gas mask test with his unit and passed without a hitch. He shouldn’t be subjected to additional, discriminatory testing because of his faith. The Army is treating him as if he were a lab rat."

Prior to 1974, Sikh Americans were allowed to serve in the U.S. military with their articles of faith intact. However, since 1981, stricter grooming regulations have required new recruits to request religious accommodations on a case-by-case basis, and only three Sikh Americans have been successful.

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