“The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people.”

Link to the Wikipedia article on the 9th Amendment to the Constitution of the United States

It is not now, but the 9th Amendment to the Constitution should be one of the greatest defenses of liberty that we have. Here is a very brief description of an interpretation that I find attractive: 

A libertarian originalist, Randy Barnett has argued that the Ninth Amendment requires what he calls a presumption of liberty. Barnett also argues that the Ninth Amendment prevents the government from invalidating a ruling by either a jury or lower court through strict interpretation of the Bill of Rights. According to Barnett, “The purpose of the Ninth Amendment was to ensure that all individual natural rights had the same stature and force after some of them were enumerated as they had before.”[13]

Randy Barnett’s key argument is that the many voters in the thirteen states who ratified the US Constitution would have understood the 9th amendment to mean that there was a personal sphere of liberty that encompassed a great deal. For example, based on the original public meaning of the 9th amendment, it wouldn’t take “penumbras” and “emanations” to see a guarantee of privacy rights in the US Constitution.  

Randy Barnett also argues that the Privileges or Immunities Clause of the 14th Amendment– “The Citizens of each State shall be entitled to all Privileges and Immunities of Citizens in the several States”–which the Supreme Court gutted in the Slaughterhouse Cases, was meant among other things to extend this presumption of liberty to actions of the states. The Supreme Court has partially restored the meaning of the Privileges or Immunities Clause by its interpretation of the Due Process Clause of the 14th amendment, but without as broad a scope of liberty. In particular, many aspects of economic liberty are no longer recognized as protected by the US Constitution.