misbiased

/mɪsˈbaɪəst/
adjective
  1. Having or showing an unfair or incorrect bias; prejudiced in a mistaken way.
    • The article was misbiased because it only presented one side of the story.
    • Her misbiased opinion of the new student came from a rumor that wasn't true.
    • The judge was misbiased by outdated information and made an unfair ruling.