Consider the following premises. For all x_7, x_7 is a police officer if and only if x_7 is a lawyer. It is late if and only if Charles is a lawyer. It is not late. Can we infer the following from them? Charles is not a police officer.
 From the fact that for all x_7, x_7 is a police officer if and only if x_7 is a lawyer we can infer that Charles is a police officer if and only if Charles is a lawyer. From the fact that it is late if and only if Charles is a lawyer, and that it is not late we can infer that Charles is not a lawyer. Finally, from the fact that Charles is a police officer if and only if Charles is a lawyer, and that Charles is not a lawyer we can infer that Charles is not a police officer. Therefore, the answer is yes.