Kindly refer to the many instances in which the Caliph had to clarify his position. Just think about an old woman openly questioning Hazrat Umar about the equitable distribution of cloth. People do have the right to question injustice, if any, in society and those responsible or accused have to clarify their position.
Causing anarchy, chaos and confusion are not allowed as they hamper harmonious discharge of official duties.
Criticism of the state is different from criticising a person.