Briggs 1 Shilling Coin

I’ve never seen one of these before and I’ve had great difficulty finding anything out about it. Has anyone seen this coin/medallion/token before, and if they have, can they tell me when and where it was produced and for what reason?

Thanks

Exonumia, not coin.

I don't know, but it's NOT a coin, maybe someone else can find the answer to your question!

What is the lettering next to the 1? I think I see “As Old Bailey” but can not make out what is on the left side.

 Looks like 

J. JOHNSON