Rand, the Martin family attorney, told CNN that Lee lost his job because he "failed to conduct a fair and impartial investigation."
"I personally thank God that he doesn't have the ability to fulfill his vision to uphold an arcane practice that has no place in our legal system," Rand said.
Asked whether he would do things differently given the opportunity, Lee, a 30-year veteran of law enforcement, said there always are things he could change in hindsight, but he stands by the investigation.
At every turn in the 40-minute interview with CNN's Howell, Lee doggedly defended his investigators, saying race never played a role in any decision and that his officers "conducted an unbiased review."
Investigators knew letting Zimmerman walk free for 46 days was an unpopular decision -- and they took abuse for it -- "but they performed professionally. That's the mark of a strong police department."
Lee took issue with the media casting his department as apathetic or lackadaisical in the case.
"A lot of the information that was given out as fact was misinformation," he said. "It was reported in some media that we didn't conduct an investigation for two weeks, but yet in that same media they would show a photograph of a crime scene with crime scene tape, with patrol cars and blue lights and investigators on the scene."
Lee shrugged off the notion that he was hired to clean up racism and other problems in the department. His goal upon becoming chief was to improve professionalism and trust, and he set several goals, all of which were met during his 10-month tenure, he said.
One of his greatest regrets, he said, is that the Zimmerman investigation ultimately shattered his childhood dream to be police chief of the community where he was raised.
"It's a dream of a vision that is going to be unrealized," he said. "I'm at peace with it on most days. I'm a man of faith. But it stings."