Posted by Orin Kerr:
Encryption, the Fifth Amendment, and Aaron Burr:
http://volokh.com/archives/archive_2007_12_23-2007_12_29.shtml#1198712224
Following [1]my posts last week on encryption and the Fifth Amendment,
a few readers asked about how courts have dealt with such issues
before. As far as I know, there is only one other judicial decision
specifically addressing the Fifth Amendment implications of decrypting
ciphertext. Remarkably, it arose 200 years ago, in the [2]treason
trial of former Vice-President Aaron Burr.
The prosecution had charged Burr with treason for leading a failed
rebellion against the United States in the western territories. The
evidence included an encrypted communication Burr had sent to his
alleged co-conspirators. To decrypt the communication, the prosecutor
subpoenaed Burr's private secretary, Willie, (who knew the key to
Burr's cryptography) and forced him to testify as to the
communication's plaintext meaning. Willie objected on Fifth Amendment
grounds.
In United States v. Burr, 25 F. Cas. 38 (C.C. Va. 1807), Chief
Justice Marshall ruled that Willie could be compelled to answer
because revealing his knowledge of the cipher would not incriminate
him. Here was Marshall's analysis:
To know and conceal the treason of another is misprision of
treason, and is punishable by law. No witness, therefore, is
compellable by law to disclose a fact which would form a necessary
and essential part of this crime. If the letter in question contain
evidence of treason, which is a fact not dependent on the testimony
of the witness before the court, and, therefore, may be proved
without the aid of his testimony; and if the witness were
acquainted with that treason when the letter was written, he may
probably be guilty of misprision of treason, and, therefore, the
court ought not to compel him to answer any question, the answer to
which might disclose his former knowledge of the contents of that
letter.
But if the letter should relate to misdemeanor and not to the
treason, the court is not apprized that a knowledge and concealment
of the misdemeanor would expose the witness to any prosecution
whatever. On this account the court was, at first, disposed to
inquire whether the letter could be deciphered, in order to
determine from its contents how far the witness could be examined
respecting it. The court was inclined to this course from
considering the question as one which might require a disclosure of
the knowledge which the witness might have had of the contents of
this letter when it was put in cipher, or when it was copied by
himself; if, indeed, such were the fact. But, on hearing the
question more particularly and precisely stated, and finding that
it refers only to the present knowledge of the cipher, it appears
to the court that the question may be answered without implicating
the witness, because his present knowledge would not, it is
believed, in a criminal prosecution, justify the inference that his
knowledge was acquired previous to this trial, or afford the means
of proving that fact.
The court is, therefore, of opinion that the witness may answer the
question now propounded.
References
1. http://volokh.com/posts/chain_1197670606.shtml
2.
http://www.orinkerr.com/2006/03/27/aaron-burr-and-antonin-scalia-acting-chief-justice/
_______________________________________________
Volokh mailing list
[email protected]
http://lists.powerblogs.com/cgi-bin/mailman/listinfo/volokh
