IMHO, no to both concerns. Even today, the lack of knowledge regarding the law is no defense. As an aside, for something to be illegal there must be a law against it, and as of yet, no one has ever pointed to a US law (or the Constitution) that prohibited secession.
In Justice Chase's Texas v White decision, he maintained the position held by Justice Story and by Lincoln, that the Constitution incorporated the "perpetual" nature of the union (overlooking the fact that a word used 5 times in the Articles was omitted, and the fact that the states seceded from the Articles). In that decision, Chase held that the state of Texas had never left the union, which renders his ruling on the payment of bond the reverse of what would be the case if Texas had not left (Justice Grier, author of the majority opinion in the Prize Cases, destroys Chase's arguments in his dissent in Texas v. White).
But back to treason. According to US code (those laws made pursuant to the Constitution) treason was defined thusly in 1790: Section 1. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That if any person or persons, owing allegiance to the United States of America, shall levy war against them, or shall adhere to their enemies, giving them aid and comfort within the United States or elsewhere, and shall be thereof convicted, on confession in open court, or on the testimony of two witnesses to the same overt act of the treason whereof he or they shall stand indicted, such person or persons shall be adjudged guilty of treason against the United States, and shall suffer death. An Act for the Punishment of Certain Crimes against the United States (1 Stat. 112, 1790)
And this by Justice James Wilson ("Of Crimes Immediately against the Community, Lectures on Law" in 1791):
[W]ho may commit treason against the United States? To this the answer is--those who owe obedience to their authority. But still another question rises before us--who are they that owe obedience to that authority? I answer-- those who receive protection from it. ... "The Confederacy did not owe allegiance to the union, nor did they receive protection from it - the Union attacked the Confederacy.A traitor is hostile to his country"
Mens rea connotes a guilty mind, or the mental state accompanying a forbidden act. For an act to constitute a criminal offense, the act usually must not only be illegal, but also be accompanied by a requisite mental state. It would be quite a challenge to show criminal intent by the act of secession.
I agree with your assessment of Texas v. White. Also, Chase strains mightily to create a definition of a State useful to his purpose.
As for the actual indictment language, I want to see the eyewitness testimony to Davis "not having the fear of God before his eyes ... but being moved and seduced by the instigation of the devil." They knew how to write back then! It looks like something produced by one of Baghdad Bob's associates.
The Life and Public Services of Salmon Portland Chase
by J.W. Schuckers, 1874
D. Appleton and Company, New York
Reprinted by Menmosyne Publishing Co., Inc. Miami, Florida
Library of Congress Catalog Card Number 73-89432
Page 534
QUOTE
Not long after, he was indicted in the Supreme Court of the District of Columbia for the crime of high-treason; but Jefferson Davis had not committed the crime of high-treason in the District of Columbia, and, although some public men hald that the commander-in-chief of the rebel armies was constructively present with all the isurgents who prosecuted war in Northern States and in the District where the indictment was found, the Government abandoned the doctrine of constructive presence as unconstitutional, and advised that the proper place for trial was Virginia.
Accordingly, at the May term (1866) of the district Court of the United States for that State, Jefferson Davis was indicted - not for the crime of high-treason - but that, "owing allegiance and fidelity to the United States of America, and not having the fear of God before his eyes, nor weighing the duty of his allegiance, but being moved and seduced by the instigation of the devil; and wickedly devising and intending the peace and tranquillity of the United States to disturb, and the government of the United States to subvert, he" did, in order to effect his "traitorous compassings, imaginings and intentions," "on the 5th day of June in the year of our Lord one thousand eight hundred and sixty-four, in the city of Richmond, in the county of Henrico and District of Virginia .... with a great multitude .... to the number of five hundred persons and upward, armed and arrayed in a warlike manner, that is to say, with cannons, muskets, pistols, swords, dirks, and other warlike weapons .... most wickedly, maliciously, and traitorously ordain, prepare, levy and carry on war against the United States, contrary to the duty of allegiance and fidelity of said Jefferson Davis" to the Constitution and the Government, and the peace and dignity of the United States.
If convicted of the offenses charged in this indictment, Jefferson Davis might be fined any sum not exceeding ten thousand dollars or be imprisoned not exceeding ten years, or both! [fn 1]
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[fn 1] The indictment against Davis was found under the act of Congress of July 17, 1862; and Judge Field, of the U.S. Supreme Court in the "Chapman case," determined at San Francisco, held that participation in rebellion after the passage of that act, as was charged against Davis, was punishable as I have stated in the text.
CLOSE QUOTE
CHAP. CXCV.
An Act to suppress Insurrection, to punish Treason and Rebellion, to seize and confiscate the Property of Rebels, and for other Purposes.
Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That every person who shall hereafter commit the crime of treason against the United States, and shall be adjudged guilty thereof, shall suffer death, and all his slaves, if any, shall be declared and made free; or, at the discretion of the court, he shall be imprisoned for not less than five years and fined not less than ten thousand dollars, and all his slaves, if any, shall be declared and made free; said fine shall be levied and collected on any or all of the property, real and personal, excluding slaves, of which the said person so convicted was the owner at the time of committing the said crime, any sale or conveyance to the contrary notwithstanding.
SEC. 2. And be it further enacted, That if any person shall hereafter incite, set on foot, assist, or engage in any rebellion or insurrection against the authority of the United States, or the laws thereof, or shall give aid or comfort thereto, or shall engage in, or give aid and comfort to, any such existing rebellion or insurrection, and be convicted thereof, such person shall be punished by imprisonment for a period not exceeding ten years, or by a fine not exceeding ten thousand dollars, and by the liberation of all his slaves, if any he have; or by both of said punishments, at the discretion of the court.
SEC. 3. And be it further enacted, That every person guilty of either of the offences described in this act shall be forever incapable and disqualified to hold any office under the United States.
SEC. 4. And be it further enacted, That this act shall not be construed in any way to affect or alter the prosecution, conviction, or punishment of any person or persons guilty of treason against the United States before the passage of this act, unless such person is convicted under this act.
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