Is it OK to lie to criminals?
In one of Kant’s writings, he poses a question about whether it is permissible to lie to someone who is intent on murder. Suppose Joe wants to murder Sam, and suppose Sam is hiding in your attic. Joe knocks on your door and asks if you know where Sam is. Should you lie to Joe? Kant is very clear that you must not lie even in this case. Note that for Kant you should try to stop Joe from killing Sam, even to the point where you might have to kill Joe.

Compare this to a case where undercover police, or detectives, lie and set up traps to catch people they suspect of being criminals. Is this right? Make sure you understand that a consequentialist like Mill will approach these questions in a way different from the way a non-consequentialist like Kant would address them. In a way, this sets up our discussion of “High Noon,” the Western movie, for week six. Some people think that when police lie to criminals, they give up the higher moral ground and are reduced to the same moral level as the criminals. Could this be part of why police sometimes go bad?

Consider also that shelters for abused women often face inquiries from abusers about whether someone (the abused) is hiding in the shelter. The policy of these shelters is to reply that as a matter of policy they do not reveal any information about who is or is not at the shelter. In other words, “Go away!” This is not a lie, and would not be a violation of Kant’s principle against lying. To say that you cannot lie is not to say that you are always bound to reveal the entire truth, if you can avoid it without lying.

No References Needed

Also this comes from the textbook- Exploring Ethics by Steven Cahn. Chapters 13, 14, 48 & 49