I'd like to draw your attention to a debate I recently became involved in with a historian friend of mine. The topic could be simply stated as -- history and historical methods in the academy, contrasted with history and historical methods in the legal academy, and the implications for American constitutional decisionmaking.

As a background, professional and casual observers of American constitutionalism alike will know that there's some debate about how the United States Constitution is to be interpreted in complex legal (and political) debates.

• The flexible perspective is generally identified with "liberal" justices, like the recently retired David Souter and the late William Brennan, and academics, like Professor Larry Tribe. This approach holds that the Constitution is not static, but sets out principles that must be interpreted in the context of evolving times. Per Chief Justice Marshall in McCulloch v. Maryland, “we must never forget that it is a constitution we are expounding," not a statute.

• The "originalist" perspective is generally identified with "conservative" practice, and most particularly, with Justice Antonin Scalia. This tradition holds that the Constitution must be interpreted as written, and with reference to historical background at the time. Where the historical record is clear on what the framers of the Constitution intended, its provisions must be given that original effect. Originalist jurists argue that this is an objective means of resolving tough cases, and that the alternative, flexible approach is too subjective to yield predictable results.

• However, in recent years, originalist theory has been challenged by writers, like Professor Akhil Reed Amar, who argue that Scalia and other originalists err in assuming that there is one true, discoverable historical narrative for every constitutional dispute. History is more complex, they argue, and it will rarely be clear what the framers of the Constitution actually intended. Because originalist decisionmaking means choosing among disparate historical narratives, it, too, lends itself to subjectivity. A great example of dueling "originalist" narratives is District of Columbia v. Heller, the recent Supreme Court case announcing a strong interpretation of the Second Amendment (right to bear arms). There, the majority and dissents both purported to be "using" originalism and history to discern what the founding generation thought about personal gun ownership. But they came to wildly different conclusions.

This is all to explain why and how history is relevant to law and constitutionalism. History, though, is just one of the tools relied upon by lawyers in constitutional disputes. Another, oddly enough, is grammar, where even minute variations of punctuation can affect the meaning of legally significant documents. There's a rich field of debate about how text and intent relate to each other, to history, and in turn, to law. (An example, from William Eskridge, is linked here.)

After I explained these theories of constitutional decisionmaking to my friend, he offered a few objections from his viewpoint as a historian. Specifically, he said, doesn't any theory of constitutional interpretation risk running into the fallacy of presentism (viewing history through a modern lens), where it tries to wring modern meaning from ancient debates? And, if grammar matters so much to some arguments -- like in the Second Amendment, where its meaning turns upon whether the first clause of the Amendment limits or explains the remainder -- isn't it also erroneous to simply assume that 2014 grammar is at all relevant to a late 18th century document?

My question to you all then is how you view U.S. constitutional law as a form of "applied history," and the historiographic methods I've outlined above. I'm very curious to hear your take.

I just got a google alert this morning for this hot little number, brand-new in reference land. What's your favorite or most-used historical reference source?

How do deal with historical works written before and after a piece of information comes to light?

For example, histories of World War 2 written before and after knowledge of the Allies breaking German Codes. Before this superior Allied convoy tactics and technology won the Battle of the Atlantic and after knowing where the u-boats would be allowed hunter-killers groups to be the right area.