an old Navy euphemism, among Naval Officers, for a formal investigation. Being at the end of the long green table without the ashtray means you are the one who’s conduct/actions is being investigated.
First heard the term when I was in Navy OCS during the late 60s.
Ah. The ashtray...I can clearly see THAT in my head. My dad was career Navy, and an ashtray and Pall Mall were never far from his hands...nor a tumbler of ice.
That is the way it was for many Navy men of that generation...:)