I read in a book that a priest may not make a person, say who confesses to murder, turn himself into the police as his penance. This book was spiritual in nature, non-fiction, and was written by a Catholic priest.
However, a couple years ago I was in an RCIA meeting with a person I was sponsoring and our parish priest was asked if if he could require a murderer to turn himself in as his act of penance. The priest told us he could, When I tried to ask him to elaborate he shut me down.
So, what is the correct answer ?