Levi E. Thompson began practicing law in Stillwater, Minnesota in 1852. He was one of the earliest settlers and attorneys in this part of Minnesota Territory. He continued to practice until shortly before his death from tuberculous on November 8, 1887, at age fifty-eight. In memorial proceedings for him in district court several days later, Judge William McCluer recalled:
"I first became acquainted with Mr. Thompson in 1856, when he had a lucrative practice and was considered the ablest lawyer in the territory, and was possessed of considerable wealth. But with the war his practice, like that of other attorneys in the northwest, went to pieces, while his fortune had been wrecked in the great panic of 1857.
"Since that time he had endeavored in a highly commendable manner to recover his losses. As a pleader, or drawer of pleadings, he had few equals and no superior in the state. Socially he was of the most kindly, genial impulses. I never was associated with him in the trial of a cause, but he was often my opponent, in which position I learned to appreciate and admire his ability."