"These two questions have by direction of Lord Palmerston been submitted to the Law Officers of the Crown, and I am directed by his Lordship to state to you the opinion of these officers for the information of Lord Glenelg.
"The Law Officers report upon the general question, that they think that no distinction should in the case contemplated, be made between the demand for Slaves or for Freemen.
"It is the opinion of the Law Officers that in every case in which there is such Evidence of criminality as, according to the terms of the Canadian Statutes, would warrant the apprehension of the accused Party, if the alleged offence had been committed in Canada, then on the requisition of the Governor of the Foreign State, the accused Party ought to be delivered up, without reference to the question as to whether he is or is not a Slave.
"The Law Officers desire however that it should be distinctly understood, that the Evidence for this Purpose must be evidence taken in Canada, upon which (if false) the Parties making it may be indicted for Perjury.
"The Law Officers remark further on this point that the 3rd Section of the Provincial Statute enables the Governor to refuse to deliver up a Party, whenever special circumstances may render it inexpedient to accede to the demand made to the Governor on such a point.
"The Law Officers, reporting upon the subject of Jesse Happy state that they do not think that there was in that case such evidence of criminality, as, according to the Laws of the Province of Upper Canada would warrant the apprehension of Jesse Happy if the offence charged had been committed in U. Canada.
"The Law Officers indeed go farther, and say that so far as there is any evidence of the Facts, what took place was not Horse Stealing according to the Laws of Upper Canada, but merely an unauthorized use of a horse, without any intention of appropriating it.
"The Law Officers conclude by, stating, that upon these grounds, they are of opinion, that Jesse Happy ought to be set at liberty, and that instructions to that effect should be sent to the Lieutenant Governor of Upper Canada."[21]
On the ninth of May Glenelg wrote to Sir George Arthur who succeeded Bond Head as Lieutenant Governor of Upper Canada, saying: "With reference to my Dispatch to Sir Francis Bond Head of the 4th December last No 255, I enclose for your information the copy of a letter from the Under Secretary of State for Foreign Affairs stating the substance of the opinion given by the Law Officers of the Crown in respect to the restitution of Fugitive Slaves who may be demanded from the Government of Upper Canada on the plea of their having committed crimes at the places from which they have fled. In conformity with the opinion of the Law Officers of the Crown I have to desire that Jessie Happy, the individual with respect to whom this question was raised shall be forthwith set at liberty."
It is impossible not to see that the very stringent rules laid down by the Law Officers of the Crown at Westminster were intended to be in favorem libertatis. Happy was released November 14th, 1837, and so far as appears from the official records no further application was ever made for the extradition of a runaway slave until after 1842. That year the well-known Ashburton Treaty was concluded[22] between Britain and the United States. This by Article X provides that "the United States and Her Britannic Majesty shall, upon mutual requisitions ... deliver up to justice all persons ... charged with murder, or assault with intent to commit murder, or piracy or arson or robbery or forgery or the utterance of forged paper...." Power was given to judges and other magistrates to issue warrants of arrest, to hear evidence and if "the evidence be deemed sufficient ... it shall be the duty of the ... judge or magistrate to certify the same to the proper executive authority that a warrant may issue for the surrender of such fugitive."