An appeal to pity is a fallacy

Fallacy

In logic and rhetoric, a fallacy is usually an incorrect argumentation in reasoning resulting in a misconception or presumption. By accident or design, fallacies may exploit emotional triggers in the listener or interlocutor , or take advantage of social relationships between people...

 in which someone tries to win support for an argument or idea by exploiting his or her opponent's feelings of pity or guilt. It is a specific kind of appeal to emotion

Appeal to emotion

Appeal to emotion is a potential fallacy which uses the manipulation of the recipient's emotions, rather than valid logic, to win an argument. The appeal to emotion fallacy uses emotions as the basis of an argument's position without factual evidence that logically supports the major ideas endorsed...

.

Examples

• "You must have graded my exam incorrectly. I studied very hard for weeks specifically because I knew my career depended on getting a good grade. If you give me a failing grade I'm ruined!"
• "Ladies and gentlemen of the jury, look at this miserable man, in a wheelchair, unable to use his legs. Could such a man really be guilty of embezzlement?"

Analysis

Recognizing an argument as an appeal to pity does not necessarily invalidate the conclusion or the
factual assertions. There may be other reasons to accept the invited conclusion, but an appeal to pity is not one of them (see also, argument from fallacy

Argument from fallacy

Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false...

).