The Manchester United manager believes bosses who are involved in illicit dealings have to be punished.
Mourinho is worried that some managers have brought the game into disrepute with their actions and believes thorough investigations are required to name the guilty and clear the innocent.
“Anyone in our job has big responsibilities and if anyone makes mistakes he has to pay for them and has to pay for it,” he said.
But Mourinho said no one should suffer if the only evidence against them is hearsay.
“What I hate and don’t accept is rumour,” he said.
“You cannot make fun with rumours as this is too serious to listen to rumours.
“You find a person, you prove a person guilty and the world has to know and you don’t have to hide anything. But the rumours are not good.”