Marshall Thomas had high expectations for those he loved. He gave them his best, and he expected nothing short of their best in return, family members said.

When things weren’t going her way, Vikki Thomas Oshirak said she’d often take the problem to her father.

“I’d tell him I was doing this and that and this isn’t working, and that isn’t working, and he’d look at me with a little smile and say, ‘Daughter, you are confusing activity with progress,’ ” she said. “Looking back, I see how he always had a plan, and he worked the plan. And if somewhere along the line, something wasn’t working out the way he wanted it to, he would revisit his plan and make adjustments.”

Marshall Thomas of Woodstock died Dec. 20 from complications due to lung cancer. He was 76. His body was cremated, and his ashes will be buried, with full military honors, at Arlington National Cemetery in the spring. SouthCare Cremation Society and Memorial Centers, Marietta, was in charge.

A native of Chicago, Mr. Thomas was a lifelong learner, his daughter said. He graduated from the University of Nebraska at Omaha with a degree in criminal justice. Mr. Thomas earned a law degree from the Augusta Law School in Augusta, Ga., but he never intended to practice, Mrs. Oshirak said.

“He just wanted to understand the law,” she said, “and that worked in his stead because if you understand the law, then you know how it works.”

Mr. Thomas went on to have a 25-year career in the military and another 20 years in the private sector, which included law enforcement, security and intelligence-related jobs. He served in the Marines during the Korean conflict and the Army during the Vietnam War. He joined the Army because there were more opportunities for advancement, his daughter said, but his heart remained with the Marines.

Mr. Thomas and his wife moved from El Segundo, Calif., to Atlanta in the '90s to be closer to family, his daughter said. The move came a few years after the 1989 earthquake that interrupted the World Series that year. “It was a good incentive for them to move,” she said with a laugh.

Mr. Thomas’ life touched many in the military, criminal justice and law enforcement communities, said Benjamin H. Thomas III, former chief of police in Senoia and retired Hapeville deputy chief. Chief Thomas said he’s always running into someone who knew his uncle during their time in the military.

“And none of them ever had a bad word to say,” Chief Thomas said. “My uncle was a giving and caring person.”

In his retirement years, Mr. Thomas’ military exterior began to soften, his daughter said. His career was “very serious, so he was very serious,” she said, “but when the grandchildren came, he changed and we all got to know him better.”

Mr. Thomas is also survived by his wife of 44 years, Ann Thompson Thomas of Woodstock; son, Marshall D. Thomas of Canton, and five grandchildren.