being 'put on the table'

Yesterday, was the first time I heard this expression. I had no clue what it meant. A colleague of mine JC mentioned that he felt that way - because another colleague put him to the task.
My rule of thumb has always been straight - don't poke your nose into something you have no clue about. Jumping right into a discussion, is not a good idea, if the topic is unfamiliar - that is common sense.
After he brought the issue up and was dressed down for it, he realised that he was 'put on the table' by the other chap. That was when I lost the grain of the conversation, because I really didn't know what that phrase implied. And so, the explanation came - it was not a phrasal verb or anything, but a direct translation from a dialect.
I'm sure many times, we have this urge to speak up for another - but I think we should read the situation carefully first. This is not saying that we don't bother at all, it's people management. There is a time to bond and there is another for healthy discussions. People will always have something to say - when they don't, it's because they've lost their voice not because they have no opinion.
We were discussing fees - a topic which we have addressed and implemented for months. Yet, it was brought up, like a fresh point in a debate. Obviously I hit the roof and by the time JC realised he was 'put on the table' by another colleague, it was too late, he got thrashed verbally for something he actually understood, before he got confused.
Bottom line is : know whose side you're on before you begin your debate