In Connecticut you need to send in a postcard with details of the deer - sex, weight, points, etc.
If the deer is taken during gun season it must be taken to a deer check station, where they will fill out the card, collect them, and send them in at the very end of the season.
My check station told me last year the state waited until summer to ask for the cards. I have not seen harvest data published by CT for a few years now and my guess is that the aggregatino of all the data gets a very low level of effort at the state level - thanks to budget problems, I'm sure.