Spades may not be led until either some player has played a spade (on the lead of another suit, of course), or the leader has nothing but spades left in hand. Playing the first spade is known as "breaking" spades.
If you play a Spade and no one else does, you win the trick. So Spades are trump cards. In this case the highest Spade wins. The game does not allow ties for first place. In the case of a tie for first, the game will continue until there is a clear winner. This is true of both games ending at a point value and timed games. Scoring
The highest card of the suit that led or the highest spade played wins the trick. If a J♥ led, then whichever player plays the highest heart wins the trick, but if a player plays a spade, the highest spade played wins the trick.
Until Spades are broken, players are not allowed to lead with a Spade, Spades are considered broken when they have been played in a previous trick because a player could not follow suit.
In fact, you cannot lead with a Spade in any trick until at least one Spade has already been played in a previous trick - which is known as “breaking Spades” in a very similar vein to “breaking Hearts” in Hearts.
A player may not lead spades until a spade has been played to trump another trick. The trick is won or taken by the player who played the highest card of the led suit, or if trumps were played, the highest trump card wins.