Almost nothing is known about Shawn or his true position. He was introduced as The Almighty Judge on High of All Beings Living and Dead for All Eternity while playing a role in Michael's neighborhood, but it is unclear whether this is his real title. He has since been shown to hold authority over Immortal Beings in The Bad Place, such as Michael and Trevor, but appears to be a direct superior to Michael with a similar interest in torturing humans, rather than a neutral judge.
When Michael was pitching his new neighborhood idea, Shawn was one of the Immortal Beings deciding whether or not they would allow it. He stated that they had in fact tried getting humans to torture each before but found it very difficult. Nevertheless he agreed to allow Michael to try and even played along in his first run attempt. After the first attempt failed he allowed Michael to try again but if he failed Michael wouldn't get a third attempt and would face retirement.
Shawn doesn't known that Michael has reboot his neighborhood over 800 times already.