Jason has short wavy brown hair, starting to be lightly streaked with grey. He has a sharp jaw, pronounced chin, but a kind mouth and eyes. He is relatively pale, brown eyes, and quite tall. He is always clean shaven, but because of that, if he doesn't have a shaver for a couple of days, he will grow a fairly substantial beard.
Jason is devoted to his job. He has no wife and no kids, so his personal life is very shallow. He can get remarkably bitter some days, but usually when it happens he will call in sick and leave the days work to his assistant. At home, he will get drunk, sleep for thirteen hours, and then come into work the next day, seeming perfectly normal. He is kind and patient with the inmates, and has grown used to working around their unpredictable actions. Life in the ER has taught him how to react well to stress situations, so he is almost always calm and collected. He has a good relationship with the rest of the staff, but none of it is particularly close and personal. Only his assistant may qualify as beyond a co-worker and closer to a friend.
Jason Calber was the oldest son in a family that had been doctors for over five generations. Therefore, he had never had any reason to wonder what would become of his life. He went into medical school at nineteen, and became Dr. Calber by age 36. However, when he was forty years old, Dr. Calber was sued for malpractice and, while the case was denied, life at the hospital where he had worked for the past twelve years became unbearable. He was unwilling to give up his license, having nothing else that he wanted to do, but he was pushed from hospital to hospital, unable to find a place where he felt comfortable and necessary. He finally settled at a private mental facility, and has been working there for the past three years.