In recent years, courts have taken an active interest in diaries kept by public officials. This has created a "chilling effect" among those who might otherwise be inclined to record their experiences for a future generation and has led some to predict that no senator in her or his right mind would ever again keep a diary. That would be most unfortunate. And it would run counter to a well-established tradition in Senate history.

The first person elected to the U.S. Senate, Pennsylvania's William Maclay, is remembered for only one thing during his service from 1789 to 1791—he kept a diary. Without it, we would know next to nothing about what went on behind the Senate's closed doors during the precedent-setting First Congress. Maclay's experience gives added force to the truism that one sure way to shape the historical record is to keep a diary. Historians will sooner turn to a richly detailed diary than plow thorough seemingly endless boxes of archived paper or computer disks.

One of the Senate's notable diary keepers began his task early in the 19th century. New Hampshire's Federalist Senator William Plumer first put quill to paper on October 17, 1803, when the Senate met in special session to consider ratification of the Louisiana Purchase treaty. Decades before the Senate made any regular effort to report its proceedings beyond the sketchy outline of its official journal, Senator Plumer kept a full record of Senate sessions until his term expired three-and-a-half years later. His diary provides unique information on the Louisiana treaty debate, including his outburst at President Thomas Jefferson for taking the Senate's approval for granted. The president, by publicly supporting the treaty before the Senate had a chance to take it up, was, in Plumer's words, destroying the Senate's "freedom of opinion."

In the 1970s, Vermont Senator George Aiken compiled and published an excellent modern-era Senate diary. Although he first came to the Senate in 1941, he did not began his diary until 1972, when he was the Senate's second most senior incumbent. He proceeded by dictating his thoughts every Saturday for 150 weeks until his retirement in 1975. He hoped, above all, that his diary would show "how events can change their appearance from week to week and how the attitude of a Senator can change with them."