New Delhi, March 9 -- Luigi Mangione, the 26-year-old accused of fatally shooting UnitedHealthcare CEO Brian Thompson, is continuing his battle against the health care industry from behind bars. In a series of emotional letters, Mangione has connected with supporters, including a mother named Karen, whose personal struggles with the health care system have deeply resonated with him.

Karen, who is fighting to afford her daughter's medical care, wrote to Mangione after seeing his perp walk in December. The letter was shared by Ashley Shelby on her Substack, Bartleby on Trial, which covers Mangione's case.

Driven by an unexplainable force, she felt compelled to reach out. In her letter, Karen recounted her difficult experiences with United...