by all rights; properly speaking; legally speaking
Used to state what should be the case according to rules, norms, or expectations, often followed by a contrast with reality. Can imply a legal or formal standard, but also used in everyday reasoning.
By all rights, I should submit the report by the end of today.
本来であれば彼が責任を取るべきだが、誰もそうは言わなかった。
Properly speaking, he should take responsibility, but no one said so.