Ditto what Headache said. If Columbo ever meant it, my whole world would collapse!
I do think that Columbo has a bit of the old-fashioned knight in shining armor in him, and he may have had particularly strong feelings about a case in which he becomes increasingly convinced that the murdered man was a user and abuser of women. Having to act the role he did, deceiving Ms. Staten, probably caused some complicated feelings for him