Aaron Rigby, with Sidley Austin.

Before Aaron Rigby embarked on a career as a transactional lawyer in the Dallas office of Sidley Austin, he had a front-row seat to history when he served for five years as surface warfare officer in the U.S. Navy.

After graduating from the U.S. Naval Academy in 1998, Rigby was on a ship near the Seychelles Islands when he acted as the security team leader sent to help the USS Cole in 2000 after the guided-missile destroyer was attacked by an Al-Qaeda suicide boat, killing 17 U.S. sailors.

And in 2001, Rigby was part of the only U.S. Navy team attached to the U.S. Marines in the Persian Gulf after the 9/11 attacks and helped lead the introduction of the first ground forces into Afghanistan during Operation Enduring Freedom.

“I knew that the military wasn’t going to be a 20-year career for me. I knew I wanted to do other things,” Rigby said. “And when my five years was up, I moved back to Dallas and went to SMU law school.”

After graduating as the valedictorian of the law school class in 2007, Rigby joined Weil Gotshal & Manges as a mergers and acquisitions lawyer but left the firm in 2013 along with 28 of his colleagues to join Sidley.

Rigby had always been encouraged by Dallas’ big firm culture to donate his time to pro bono projects, and he gravitated toward helping former veterans like himself. And he found that he was an even better fit at Sidley, which already had a pro bono project to assist veterans in accessing and appealing the Department of Veterans Affairs administrative decisions on disability payments.

“I think people, whether its law or a professional career that has a niche, have a moral obligation to use their education to help other people,” Rigby said. “It’s certainly encouraged at Sidley to find an area you’re interested in and volunteer, but personally and morally, I think it’s something I ought to do.’’

On Nov. 16, Rigby’s law firm is holding a free clinic to assist retired military veterans about their eligibility for combat-related special compensation pay, which is available to vets who have a 10 percent or higher disability rating due to military service.

Rigby and other Sidley attorneys also regularly staff the Dallas Volunteer Attorney Association’s legal clinics at Dallas’ VA Hospital, where veterans can get free help with benefits, consumer, employment, housing, landlord-tenant, bankruptcy and probate cases.

Earlier this year, Rigby and Sidley received the Dallas Volunteer Attorney Program’s “Gold Award” for pro bono work, part of which included the work they did for vets. The firm has already logged 5,000 hours this year and is on pace for 7,000 by the end of the year.

And Rigby also serves as the pro bono general counsel for the Carry the Load Foundation, a charitable organization supporting education and rehabilitation for military veterans and first responders that was started by two of Rigby’s Naval Academy classmates.

“I’ve seen the impact that organization can achieve with our legal help,” said Rigby, who does contract and fundraising work for the organization and sits on its board of directors. “They can grow and expand because of some of the work we’ve done for them.’’