Do I have to answer the door if an officer is knocking but no warrant?

If an officer knocks at my door and wants me to open it, can anything happen to me if I do not answer the door?
i.e. one night there was a party nextdoor and he came nextdoor to question me about it because he thought i was part of the party. He saw me in there and kept knocking until i answered. I got the short end of the stick thanks to him and was wondering, if it happens next time, if I have to answer the door?

dont open the door

in this time and days you dont have to open the door for anyone. anymore we dont even have to let our kis in if we dont want to. if thay have a warent thay can open the door anyway thay have to, but you never have to open a door if you dont want to.