undue

Etymology

From un- + due.

adj

1. Excessive; going beyond that what is natural or sufficient.
   To individuals who despise killings in any form, death penalty is undue punishment.
   But even if they don’t announce themselves on the cover of the Times business section, groups of millionaires exercise undue influence on every aspect of American life every day. January 17 2016, “Wealthy cabals run America”, in Al Jazeera America, retrieved 2016-01-18
2. That which ought not to be done; illegal; unjustified.
3. (of a payment etc) Not owing or payable.