The manslaughter trial of former Marine Daniel Penny for choking a homeless man who was scaring subway riders reflects the considerable divisions in our world today. To some, Penny is an urban hero — a good Samaritan — who risked his own safety to protect vulnerable subway riders. To others he is just a racist white man who is guilty of yet “another lynching of a Black man.” These extreme views hide the complexities not only of this particular case but of the law regarding the right of citizens to use force to protect other citizens.