give somebody the benefit of the doubt

Từ điển tiếng Anh - Cambridge Advanced Learners Dictionary

give sb the benefit of the doubt idiom
to believe something good about someone, rather than something bad, when you have the possibility of doing either
• I didn't know whether his story was true or not, but I decided to give him the benefit of the doubt.
Thesaurus⁺: ↑Believing
Main entry: benefit_idiom