MacReady was a Human sheriff on the Skagaran planet, where a population of about 6,000 Humans lived.
MacReady was a reasonable man, but still believed that the "Skags" needed to be kept in check in order to protect the Humans. He enforced laws that prevented Skagarans from owning property or being educated. When Jonathan Archer visited the planet during the Xindi mission, he intervened and stopped an abuse of a Skagaran. MacReady told Archer to leave town. After Archer saved a local school teacher, he returned to the planet in a shuttlepod to have a meeting with MacReady. The sheriff believed Archer's story and was preparing to visit Enterprise when one his deputies attacked and wounded MacReady. They were able to stop the deputies, and MacReady agreed to make changes in the treatment of the Skaragans. Archer promised him that he would return the Humans to Earth after the Xindi mission. (ENT: "North Star")