From Longman Dictionary of Contemporary Englishbe open to question/doubtbe open to question/doubtNOT SUREif something is open to question, there are doubts about it Whether the new situation is an improvement is open to question. → open
Examples from the Corpus
be open to question/doubt• The authenticity of the relics is open to doubt.• Whether this kind of Labour Party is capable of winning a general election is open to doubt.• Their motives are open to question.• But whether Republicans want to cooperate is open to question.• In particular, the significance of the small number who say their work has been deskilled is open to question.• The entire business of basing regulations on animal tests is open to question.• The President acceded to the Chancellor's request for two reasons, both of which were open to question.• Whether the yeast could ever be as abundant as this is open to question.• It also is open to question how well equipped courts are to make this kind of determination-about the workings of economic markets.• Even if, as is open to question, screen violence really does invite emulation, that is the wrong approach. 