He is the older brother of criminal defence lawyer and convicted criminal Jimmy McGill , and the ex-husband of Rebecca Bois. Chuck is a highly intelligent and dedicated lawyer who views the law as being sacred, and is very determined in helping his clients in any way possible. However, by , Chuck began to claim to suffer from electromagnetic hypersensitivity EHS , essentially an adverse physical reaction to electrical devices, which make it challenging for him to lead a normal life.
After Chuck steps away from HHM due to his claim of electromagnetic hypersensitivity, Howard enables him to work from home while Jimmy takes care of Chuck's personal needs.
Despite Jimmy admiring his older brother and initially believing him to be supportive of him as a lawyer, Chuck reveals to greatly resent his brother for his past actions as a conman, and believes him to be completely unfit to be a lawyer.
Chuck prevents Jimmy from being hired by HHM and proceeded to create a majority of the obstacles he faces early on in his career. Chuck has a tumultuous and complicated relationship with Jimmy, with the two brothers often not seeing eye to eye and Chuck having conflicting views on how he feels about Jimmy, and he is unintentionally largely responsible for turning Jimmy into the criminally-inclined lawyer Saul Goodman that he later becomes. Chuck is certain Jimmy sabotaged him and plans to get revenge.
He secretly records Jimmy's admission to tampering with the Mesa Verde documents, then makes Jimmy aware of the recording. When Jimmy breaks in to destroy it, Howard is present and serves as Chuck's corroborating witness. Chuck presents the confession to the state bar association in hopes of having Jimmy disbarred, but Jimmy and Kim minimize Chuck's argument by exposing his alleged electromagnetic hypersensitivity as a psychosomatic ailment. Jimmy's law license is suspended but he is not disbarred.
