I have been invited to take a tour of Canada by British Maj. Gen. Charles Hastings Doyle.  While there, I took the opportunity to look into legal matters concerning Confederates who had fled to Canada during the war.  I wrote Sec. Stanton,

Montreal Canada Aug. 8th 1865

Hon. E. M. Stanton,

Secretary of War,

Sir:
Since my arrival here I have seen Mr. Potter, our Consul and find that in his judgment after investigation that the charges made against Dr. Montrose Pollen of trying to extort from a witness in the conspiracy trial a contradiction of his testimony in the case is probably without foundation. As amnesty had been extended to Dr. Pollen, and was revoked in consequence of the charge I would respectfully recommend that he be paroled to go to St. Louis, to await whatever action may be thought necessary in his case. I would also recommend that Mr. Potter our Consul be authorized to parole Gen’l D. M. Frost to go to St. Louis to await action in his case: General Frost voluntarily went before the American Consul at Quebec and took the proper steps and Oath for making his application for Amnesty.
Very respectfully
Your obt. Servt
U. S. Grant
Lieut Gen’l

The Papers of Ulysses S Grant, Vol 15, p 291