No offense, stevep, but I hope you are wrong or he gave a dying declaration!
Even if Henry Parker gave a dying declaration, it would have two huge legal problems.
1) It's not a dying declaration about Henry Parker's Murder (and he was not murdered) and
2) It's not a dying declaration made in a "police emergency," such as when he was dying after being shot.
http://caselaw.findlaw.com/us-supreme-court/09-150.html
is a fairly recent, 2011 Supreme Court Case, where it looks like they had to bend backwards to not call testimony "testimony" so it would not violate the Constitution, in my opinion.
Of course prosecutors often push the limits of using evidence, which is why so many cases are overturned.