Poor or unfair conduct by a public body that may be lawful but falls short of good administration, such as unreasonable delay, rudeness, failure to follow procedures, bias or neglect.
In more detail
Maladministration is the core concern of ombudsman institutions, which fill the gap between illegality, which courts can address, and simple dissatisfaction. The European Ombudsman defines it broadly as occurring when a public body fails to act in accordance with a rule or principle that is binding on it, including principles of good administration and respect for fundamental rights. Because the concept is open-ended, ombudsmen develop codes of good administrative behaviour to give it content.