Most famous for his 2006 work Fish: A Memoir of a Boy in a Man's Prison, Parsell also published a New York Times article titled "Unsafe Behind Bars" and contributed to such documentary films as Teenage & Homeless in America and Avoiding Sexual Assault in Prison.
In his late teens, he served prison time for robbing a photo booth with the aid of a fake gun.
An activist as well as a writer, he headed a Los Angeles-based organization called Just Detention International. After being released from prison, he earned a bachelor's degree from New York City's St. Francis College. He later pursued an advanced degree in television and film at New York University's renowned Tisch School of the Arts.
He was born and raised in Dearborn, Michigan.
He and New Mexico-born writer Jimmy Santiago Baca both wrote prison memoirs.