What's the rule?

[tankslapper 1]

This happened to me a little while back. I wanted to get an opinion as to how it should have been handled.

I am heads up against one other player. I have J-8. Flop comes out 7,8,10. He bets, I call. Turn is a 2. He bets, I call. River is a 7. I had put my opponent on a straight draw, so when he made a big river bet, I called. I asked what he had, he says "trip 7's". I said, if you do, you win. My cards were face down on the table, but not in the muck. Dealer never touched my cards. When he flipped over his cards, he showed A-9. I said you are a liar and flipped over my cards showing I had a pair and won the hand. He made a big stink saying I already conceded and my cards were mucked. This was supposed to be a friendly home game and an argument started. The dealer, in an effort to keep the peace, chopped the pot. 

I was under the impression that 1: since I called his river bet and we were at showdown, his verbal comment was binding. Him mis-representing his hand would be cause for him to forfeit it. And 2: since my cards were never in the muck, they were still live. 

Any thoughts?

[FCP Bob 1,312]

the other player is an angle shooting POS and the dealer doesn't know how to stop it.

You 100% should have won the pot not because he lied about his hand but because your hand beat his and you're right that you hand for sure was still live.

A lesson to learn though. Always keep hold of your cards and wait until you see the other player's hand before mucking or doing anything to concede the pot. I wish players would just open up their hands when they're called, it keeps the game moving and keeps this sort of crap from happening.