Regarding CJ Taney and the Merryman ruling, on page 17 of Lincoln's Constitution Daniel Farber asserts, "Technically, he did not issue it in his capacity as a judge 'on circuit' but rather as an 'in chambers' opinion of the chief justice."
There is support for Farber's assertion in the closing of the Merryman ruling:
In such a case, my duty was too plain to be mistaken. I have exercised all the power which the constitution and laws confer upon me, but that power has been resisted by a force too strong for me to overcome. It is possible that the officer who has incurred this grave responsibility may have misunderstood his instructions, and exceeded the authority intended to be given him; I shall, therefore, order all the proceedings in this case, with my opinion, to be filed and recorded in the circuit court of the United States for the district of Maryland, and direct the clerk to transmit a copy, under seal, to the president of the United States. It will then remain for that high officer, in fulfilment of his constitutional obligation to 'take care that the laws be faithfully executed,' to determine what measures he will take to cause the civil process of the United States to be respected and enforced.
If Taney were not writing from the Supreme Court, there would seem to be no need for him to order all the proceedings, with his opinion, to be filed and recorded in the circuit court of the United States for the district of Maryland.
It should be noted that Lincoln did NOT suspend habeas in the Merryman case. Lincoln authorized General Scott to suspend habeas at his discretion. General Scott further delegated the authority to suspend habeas. The order to suspend habeas came from General Keim in Pennsylvania.
Notice the recognition of this from the holding in Merryman:
Held, that the petitioner was entitled to be set at liberty and discharged immediately from confinement, upon the grounds following:
1. That the president, under the constitution of the United States, cannot suspend the privilege of the writ of habeas corpus, nor authorize a military officer to do it.
The arrest and imprisonment of Merryman was obviously unlawful if Lincoln lacked authority to suspend habeas. But it was also unlawful if Lincoln could not lawfully delegate authority to suspend habeas. Further, it was unlawful if General Scott could not lawfully delegate authority to suspect habeas to General Keim.
It was General Keim who actually ordered the suspension of habeas on a claim of delegated authority. To show that the arrest and imprisonment of Merryman was lawful, one must show that General Keim had the lawful authority to suspend habeas.
Thanks for the info.