Ron was feeding Hagrid's dragon. Afterwards He says:
やつが僕の手をかんだというのに、僕がやつを恐がらせたからだって叱るんだ。(Harry Potter, Japanese TL)
Even though the thing bit my hand, he (Hagrid) scolded me saying that I'd scared it. (My TL)
When it bit me he told me off for frightening it. (Original text)
I'm confused by the end of this sentence, 叱るんだ. I expected this to be in past tense i.e. 叱った(んだ). I thought that perhaps it was past tense and there was a verb しかる(む/ぶ), but that doesn't seem to be the case. So I'm left with a present tense verb + explanatory-の + だ, and that somehow conveys the past tense?? What am I missing here?
