It's the most familiar part of the Constitution - the one that the most people can quote. It's the most disputed part of the Constitution - the one whose meaning is most debated. And it's the most tangible part of the Constitution - the one that writes into stone the rights we use every day, and which is thus easiest to apply to everyday life.
The Constitutional Convention
The portion is, of course, the Bill of Rights; but it was not a part of the original Constitution at all. The United States Bill of Rights was the first ten amendments to the Constitution; and for those who don't know, an amendment is just another word for a change. The Constitution has been amended (or changed) 27 times since its adoption; and the first ten amendments written into it were the ones we today call our "Bill of Rights." They can today be seen in the context of the ratification debates; or the debates over whether or not to ratify the Constitution as the supreme law of the land. The Constitution did not become law until it was approved by nine of the original thirteen states, and it was fiercely debated whether or not we should have this Constitution.
The biggest objection to the Constitution during the ratification debates was precisely that it lacked a Bill of Rights. Although Alexander Hamilton deals with this objection in the Federalist Papers by saying that there was no need for a Bill of Rights, because all of the thirteen states already had one; James Madison never disagrees with the need for one in the Federalist Papers. (I'm not blaming Alexander Hamilton for arguing the wrong side of this issue; because even though I disagree with what he said, I think it was more important for him to argue for the Constitution at that time than to attack its greatest weakness.) But James Madison, quite interestingly, asks rhetorically if "a bill of rights [is] essential to liberty," and follows it up by saying that "The Confederation has no bill of rights" (Source: Federalist No. 38) - pointing out the irony of opposing the Constitution for lacking a Bill of Rights, when the existing system of government (today called the Articles of Confederation) had no Bill of Rights either.
The opponents of the Constitution were, of course, right that the document needed a Bill of Rights; and it was probably more important for it to have one than it was for the weaker Articles of Confederation to have one, because the Articles had less power in government that needed to be checked in this way. But ironically, it was the Father of the Constitution himself - James Madison - who wrote the Bill of Rights (rather than the objectors to the Constitution, who had argued so strenuously against the Constitution for its lacking such a bill). It's a measure of how much the pro-Constitution side won the debate, that the only concession the Constitution's opponents got after the document was ratified - namely, the Bill of Rights - was written not only by a pro-Constitution person, but by the Father of the Constitution himself. The pro-Constitution side won the debate. Nonetheless, we owe a great deal to the opponents of the Constitution for ensuring that we got a Bill of Rights; because they were absolutely right that the document needed one, and we are protected today by its stipulations.
United States Bill of Rights
Like all constitutional amendments, the Bill of Rights had to go through a difficult amendment process before it became a part of the original Constitution; and it is largely due to the Constitution's opponents of that time that we have one today. This amendment process is found in Article V of the original Constitution, and reads as follows: "The Congress, whenever two thirds of both houses shall deem it necessary, shall propose amendments to this Constitution, or, on the application of the legislatures of two thirds of the several states, shall call a convention for proposing amendments, which, in either case, shall be valid to all intents and purposes, as part of this Constitution, when ratified by the legislatures of three fourths of the several states, or by conventions in three fourths thereof, as the one or the other mode of ratification may be proposed by the Congress." The article then ends with the two officially mandated exceptions to this, one of which said that two portions of the original Constitution that protected slavery could not be changed before the year 1808 (twenty years afterward), and the other of which said that "no state, without its consent, shall be deprived of its equal suffrage in the Senate." (Source: Article V) The Bill of Rights did not fall under either of these two exceptions, and so was ratified as the law of the land on December 15, 1791, with all ten amendments ratified simultaneously.
U.S. Supreme Court
Today, the Bill of Rights is the part of the Constitution that is most debated: From debates over free speech and freedom of the press, to debates over the rights of the accused in a trial, there is not a single portion of the Bill of Rights that hasn't been debated time and time again since the amendments were ratified; and interpreted by Supreme Court cases (good and bad) at some point or another - usually many points. I won't go into the specifics of the debates, or how the amendments' meaning has been distorted; but there is scarcely a portion of the Bill of Rights (or any other portion of the Constitution, for that matter) that is not under attack by liberals. From the gun control policies violating the Second Amendment to attacks on religious rights protected in the First, the Bill of Rights is much under attack by liberals; and its meaning has been distorted (deliberately and otherwise) by the many judges of the left. This is a problem among liberals generally and judges specifically - that they are willing to throw out the meaning of the Constitution, in favor of advancement of their agendas and social policies.
Original Constitution of the United States
I won't go into any part of the Constitution specifically (at least not more than I already have), but let me end this post with a plug for strict construction of the Constitution - a following of the words' meanings to the letter, without consideration of their meanings as "flexible" and "adaptable to the times." The only things in the Constitution that were meant to be "adapted to the times" were those changes that were made in accordance with the original amendment process, in Article V of the original Constitution. The Constitution gives discretionary power in certain areas about how to apply the policies it gives, but to say that the explicit statements made in other parts can be "adapted" to mean whatever you want is to deny the reality that words mean things. Denial of this reality is the defining characteristic of liberal interpretation of the Constitution, and one they are forced to make from the reality that their interpretations of the Constitution just don't hold water.
There's a need for strict construction of the Constitution today, and for judges that will interpret it as it was written. This is true of all parts of the Constitution, but perhaps nowhere moreso than in the disputed Bill of Rights.
If you liked this post, you might also like:
The Constitutional Convention
The United States Constitution
The ratification debates
Part of a series about
The Constitution itself, and the story behind it
Convention at Philadelphia: The writing of the Constitution (1787)
Preamble: The Constitution's mission statement, with some thoughts about separation of powers
The Congress: Its power to make laws, and the president's power to veto them (in some cases)
Frequency of elections: So how long do all of these people serve, anyway?
Representation: So who decides how many votes each state gets?
Slavery: The complicated legacy of the "Three-Fifths Clause"
The presidency: Powers of the executive, and their being subject to impeachment
The courts: "Good behaviour," some important judicial powers, and how they're appointed
Miscellaneous: Amendment process, "supreme law of the land," and some closing remarks
Debates over the Constitution, then and since
Debates over ratification: Whether to adopt the Constitution in the first place
The "Federalist Papers": Frequently asked questions about them, and why they're important
Debates over checks & balances: Do they actually conflict with separation of powers?
The Bill of Rights: Important in the debates over ratification (adopted 1791)
The Constitution today: Some thoughts about civics education