You can't just lead a spade whenever you want. Spades are trump, and trumps are protected by a rule that says nobody leads them until somebody else 'breaks' them by cutting into a non-spade lead. It's a simple rule with big strategic consequences in JJDD.
What 'broken' actually means
Spades are broken as soon as one has been played to a non-spade lead. Somebody leads a heart, somebody else is void in hearts and drops a spade to cut — that's a break. From that book onward, any player can lead a spade.
Until they're broken, you can only lead a spade if that's the only suit you have. Otherwise you have to lead hearts, diamonds, or clubs.
The Jokers and Power 2s count as spades
The Big Joker, Little Joker, and 2♦ all cut like spades even though they don't look like spades. Playing any of them on a non-spade lead breaks spades — including the 2♦, even though it's technically a diamond in suit.
This matters because a player with a Joker but no other spade is not restricted from leading it once spades are broken. Some players forget the Jokers count as spades and get caught leading them into a trap.
Strategic breaks
Breaking spades early is a tool. If you're the team ahead in trumps, breaking gets more spades onto the table, which favors the team with the most and highest spades. If you're short on trumps, delay the break — every non-spade book you win keeps your low spades useful as cuts later.
Watch the table. If nobody has cut a lead through two full rounds, somebody at the table is short in every suit and holding for a moment. That's often the tell for a big spade hand about to make a move.
