In the Royal Navy the punishment prescribed for most serious crimes was flogging. This was administered by the Bosun’s Mate using a whip called a cat o’ nine tails. The “cat” was kept in a leather or baize bag. It was considered bad news indeed when the cat was let out of the bag.








So how did that come to mean spilling the beans?
Maybe when you release the cat on a person they would spill the beans as a result?