Showing Cards/Mucking Rules

Sorry if this sounds a dumb question but I usually play online poker and when a player mucks check the HH to see what they called with!

I am playing live tonight and want to know the rules on showing.

For example, if I reach show down and its a stone cold bluff can I muck instantly and give the pot to the player. Or like, if I show and a player says I have him beat can I demand to see the cards he is mucking..


Thanks

If you are called, you should show your hand first in the showdown. However, I've noticed a lot of the players I play with live are so eager to show their hands that they flip their cards over as soon as they call me and their chips get in the pot. If I'm bluffing or have the losing hand I muck my cards as fast as I can. I figure it's their fault for not making me show first when they call me and once the cards are in the muck, they're gone.

But if I call a player on the river, I ALWAYS make them show first.

Not positive if this is how it is, but the way we play live is that to win the pot, the person with last action (bet or raise) has to show. If the other person shows first, they can muck, or if it was a stone cold bluff, they have the board or something, they can muck without seeing the other hand. They risk mucking the best hand or mucking when it's a chop, but they are allowed to do that. Not sure about in casinos and such, and if it's a home game, it's anyone's guess.

The one question I have, is if the river is checked down. 2 possibilities.

1. Absolutely no action, just some calls of the blinds PF and checks all the way through
2. action on flop and/or turn, no action on river.

In #2, does the person last to act on the turn (and if no action on turn the river) have to show first? And how does it work in #1? Thanks.

From Robert's Rules of Poker:

ROBERTS RULES OF POKER

THE SHOWDOWN
1. A player must show all cards in the hand face-up on the table to win any part of the pot.
2. Cards speak (cards read for themselves). The dealer assists in reading hands, but players are responsible for holding onto their cards until the winner is declared. Although verbal declarations as to the contents of a hand are not binding, deliberately miscalling a hand with the intent of causing another player to discard a winning hand is unethical and may result in forfeiture of the pot. (For more information on miscalling a hand see “Section 11 - Lowball,” Rule 15 and Rule 16.)
3. Any player, dealer, or floorperson who sees an incorrect amount of chips put into the pot, or an error about to be made in awarding a pot, has an ethical obligation to point out the error. Please help us keep mistakes of this nature to a minimum.
4. All losing hands will be killed by the dealer before a pot is awarded.
5. Any player who has been dealt in may request to see any hand that has been called, even if the opponent's hand or the winning hand has been mucked. However, this is a privilege that may be revoked if abused. If a player other than the pot winner asks to see a hand that has been folded, that hand is dead. If the winning player asks to see a losing player’s hand, both hands are live, and the best hand wins.
6. If you show cards to an active player during a deal, any player at the table has the right to see those exposed cards. Cards shown during or after a deal to a player not in the pot should be shown to all players when the deal is finished.
7. If everyone checks (or is all-in) on the final betting round, the player who acted first is the first to show the hand. If there is wagering on the final betting round, the last player to take aggressive action by a bet or raise is the first to show the hand. In order to speed up the game, a player holding a probable winner is encouraged to show the hand without delay. If there is a side pot, players involved in the side pot should show their hands before anyone who is all-in for only the main pot.