From Longman Dictionary of Contemporary Englishbe above suspicion/reproach/criticism etcbe above suspicion/reproach/criticism etcGOOD/MORALto be so good that no one can doubt or criticize you Even the king’s closest advisers were not above suspicion. → above
Examples from the Corpus
be above suspicion/reproach/criticism etc• You must be above suspicion of any impropriety.• The motives were above reproach since a large sum was raised for deserving charities every year. 