Ad hominem

Name of fallacy Ad hominem
Aliases Argumentum ad hominem, argument toward the person, argument against the person, The Fallacy of Personal Attack
Type Irrelevant Argument, Informal Argument
Description    An argument that attacks the person who holds a view or advances an argument, rather than commenting on the view or responding to the argument.
Example "You claim that this man is innocent, but you cannot be trusted since you are a criminal as well."
FormAn ad hominem argument has the basic form:

Person 1 makes claim X
There is something objectionable about person 1
Therefore claim X is false

Treatment Point out the that the individual is being attacked not the argument and that this has no relevance to the deductive logic of the  core argument and to physical world evidence.