Every defense lawyer worth his salt would advise Mr. Chu against making any statement that might possibly be construed as an admission of guilt or anything resembling and admission of guilt.
The clever witness who might incriminate himself, but does not want to invoke his 5th Amendment right since that might in some cases arouse more suspicion of there being a good case against him - and who is also trying to prevent blame from going up to his boss, i.e., fall on his sword - is walking a fine line. He is trying to avoid providing any information that implicates anyone else or himself, but still answer questions satisfactorily enough to have the hearing run out of steam. He is trying to avoid prosecution of himself, if possible, while answering things so that the investigation just ends.
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