I am sure about the crime-fraud exception to attorney client privilege, and Tom was definitely involved in crimes (of course if they didnt have proof that would be something else).
If they had Tom listed as a consigliere, and as high up on the chart as he was, I think they could have subpoeaned him.
"Io sono stanco, sono imbigliato, and I wan't everyone here to know, there ain't gonna be no trouble from me..Don Corleone..Cicc' a port!"
"I stood in the courtroom like a fool."
"I am Constanza: Lord of the idiots."
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