Evasion is, in ethics, an act that deceives by stating a true statement that is irrelevant or leads to a false conclusion.
For instance, a man knows that another man is in a room in the building because he heard him, but in answer to a question, says, "I have not seen him," thereby falsely implying that he does not know.
It is argued for as a way to fulfill both the obligations of telling the truth and of, in justice, keeping secrets from those not entitled to know the truth, but is regarded as unjustifiable without grave reason for withholding the truth.
Bull identified the following evasion techniques for answering questions: 
- Ignoring the question
- Acknowledging the question without answering it
- Questioning the question by:
- requesting clarification
- reflecting the question back to the questioner, for example saying "you tell me"
- Attacking the question by saying:
- "the question fails to address the important issue"
- "the question is hypothetical or speculative"
- "the question is based on a false premise"
- "the question is factually inaccurate"
- "the question includes a misquotation"
- "the question includes a quotation taken out of context"
- "the question is objectionable"
- "the question is based on a false alternative"
- Attacking the questioner
- Declining to answer by:
- refusing on grounds of inability
- being unwilling to answer
- saying "I can't speak for someone else"
- deferring answer, saying " it is not possible to answer the question for the time being"
- pleading ignorance
- Bull, Peter The Microanalysis of Political Communication: Claptrap and Ambiguity (2003)