No it can't. That is a deliberately dishonest reading of the intentions of the Signatories to the Declaration of Independence. If it was their intent to include slaves in the declaration, they would have freed their own slaves. As Justice Taney correctly stated, the Declaration was not comprehended as applying to slaves.
You also cannot assert the constitution intended to give freedom to slaves, because it specifically includes protections for slavery in Article IV section 2.
No Person held to Service or Labour in one State, under the Laws thereof, escaping into another, shall, in Consequence of any Law or Regulation therein, be discharged from such Service or Labour, but shall be delivered up on Claim of the Party to whom such Service or Labour may be due.
Interestingly enough, this is in the exact same article of the constitution that requires "full faith and credit" for the acts of other states, meaning other state laws regarding slavery. It's as if the founders were signaling that the "full faith and credit" must apply to slavery, because protecting the labor laws of other states was what was immediately mentioned right after the "full faith and credit" clause.
Sure, but it is pure perversion for you to argue with Taney that the Constitution & Founders intended states had no rights to abolish slavery and African-Americans no rights to citizenship.
Clearly that was not the case, even in 1776, much less in 1787 or 1857!
Shall I go on? I don't know. Thought at first you were at least a reasonable guy.
Guess I'll say this: if it could be shown that the signers of the Dof I did not intend Life, Liberty, and Pursuits to include slaves, then that would weigh in favor of Congress not having power to exclude slavery from territories.
You need to pay attention. I never said the Constitution "intended to give freedom to slaves." Just the opposite. I said the Constitution allowed slavery and until the 13th-15th Amendments, slavery was a states' issue.
Even if territories were found to be slave-free zones so to speak, I don't believe that would give the territory the right to take away the slave-owner's property. It seems to me that if a state had to give full GF&C to another state that a territory would also be bound to give a state full GF&C.
So whether a territory was slave free or not, I think Dred Scott was properly decided certain questionable parts of the opinion notwithstanding.