justifiably
adv.in a way that is fair, right, or based on good reasons. You use this when someone does something because they have a good excuse or a strong reason.
adv.in a manner that is morally, legally, or logically sound; based on valid reasons. Often modifies verbs of action or adjectives describing a state of being.
“The manager justifiably fired the employee for breaking the rules.”
“The residents justifiably complained about the noise because the construction work started before the agreed time.”
“The defense attorney argued that the suspect justifiably feared for his life, though the prosecution maintained that the level of force used was excessive.”
“It would be nice if everything here was as good as those two songs, if you could justifiably claim Second Song as an autumn-years masterpiece along the lines of Dylan’s Rough and Rowdy Ways.”
“Conor Gallagher and Lucas Bergvall did not return after the half-time interval, although they might justifiably point out others could have accompanied them.”
From justifiable + -ly.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.