Another possible reason: By having Tom appear as his counsel of record before the Committee, Tom could invoke client/attorney privilege. The FBI chart showed Tom as consigliere of the Corleone Family. He might have been called as a material witness if someone else had represented Michael.
Ntra la porta tua lu sangu � sparsu,
E nun me mporta si ce muoru accisu...
E s'iddu muoru e vaju mparadisu
Si nun ce truovo a ttia, mancu ce trasu.
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