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malfeasance vs. misfeasance

[mal-fee-zuhns] / mælˈfi zəns /

noun

Law.
  1. the performance of an act that is legally unjustified, harmful, or contrary to law, especially by a public official or a person in a position of public trust.

[mis-fee-zuhns] / mɪsˈfi zəns /

noun

Law.
  1. a wrong, actual or alleged, arising from or consisting of affirmative action.

  2. the wrongful performance of a normally lawful act; the wrongful and injurious exercise of lawful authority.