Dumbledore lied to Minister Fudge in OoP
From OoP, chapter 28
'Dumbledore's Army, Cornelius,' said Dumbledore, still smiling as he waved the list of names before Fudge's face. 'Not Potter's Army. Dumbledore's Army.'
'But - but -' Understanding blazed suddenly in Fudges face. He took a horrified step backwards, yelped, and jumped out of the fire again. 'You?' he whispered, stamping again on his smouldering cloak.
'That's right,' said Dumbledore pleasantly.
'You organised this?'
'I did,' said Dumbledore.
'You recruited these students for - for your army?
'Tonight was supposed to be the first meeting,' said Dumbledore, nodding. 'Merely to see whether they would be interested in joining me. I see now that it was a mistake to invite Miss Edgecombe, of course.'
Marietta nodded. Fudge looked from her to Dumbledore, his chest swelling.
'Then you have been plotting against me!' he yelled.
'That's right,' said Dumbledore cheerfully.