2nd amendment actually says "life, liberty, and property". Interesting that I don't know where "pursuit of happiness" came from. I'll check it out. Almost like the pledge of allegiance, which originally did not "under God" in it.
To be fair, the constitution simply reserves powers for the federal government; this doesn't mean that states and the federal government have to execute criminals. On the other hand, history and this passage indicate that our founding fathers and their descendants did use capital punishment.
There seems to be an almost effeminate apprehension toward execution of heinous criminals. I attribute this to the loss of consistent morals that the 20th century and post-modernism have brought us.
Amendment V
No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a grand jury, except in cases arising in the land or naval forces, or in the militia, when in actual service in time of war or public danger; nor shall any person be subject for the same offense to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.
He expressed the radical view that government is morally obliged to serve people, namely by protecting life, liberty, and property. He explained the principle of checks and balances to limit government power. He favored representative government and a rule of law. He denounced tyranny. He insisted that when government violates individual rights, people may legitimately rebel. --Jim Powell at the Foundation for Economic Education.