RUTHFULLY YOURS

Marshall’s modest origins hardly hinted at the illustrious career that was in store. Born in 1755, the future chief justice grew up on what was then the Virginia frontier, the eldest of 15 children who lived packed into a two-room log cabin. His father worked as a farmer and surveyor. In contrast to the tutored sons of Virginia’s elite, young John was largely self-taught. He received only a single year of formal education and later six weeks of training in the law under the eminent legal teacher George Wythe.

As a rifleman during the Revolutionary War, Marshall endured the horrific winter at Valley Forge, where he came to know George Washington. Washington sensed Marshall’s natural intellect and appointed him a military judge advocate. After the war, Marshall established a law practice in Richmond and was elected to the Virginia legislature, where he soon became the star of its Federalist minority.

Recognized by his party as a leader of national caliber, Marshall was tapped by John Adams’s Federalist administration to serve as one of three American envoys sent to Europe in 1797 in an effort to find a formula for peace during the so-called Quasi-War with France. The failed mission became known as the “XYZ Affair”—the letters were Adams’s way of cloaking the names of conspiring French diplomats—when it was revealed that the French foreign minister had demanded a bribe. The scandalous tale, which Mr. Paul unravels colorfully, involved secret meetings, veiled threats and even a femme fatale. Marshall emerged from it all as a model of probity for his adamant refusal to countenance the bribe.

He went on to win election to Congress, in 1798, and then briefly to serve as secretary of state in the waning months of the Adams administration. Then, in one of Adams’s last acts as president, in January 1801, he appointed Marshall to the Supreme Court, denying the furious incoming president, Thomas Jefferson, the chance to name his own chief justice.

Service on the court was not only an intellectual challenge; it was also a physical ordeal. When the court was in session in Washington, the justices lived together in the same hotel, rather like a fraternity. For several months a year, however, they were required to “ride circuit” in the hinterland on awful roads and share rooms with strangers in country inns. It is hard to assess the toll that the long absences from home may have taken on Marshall’s family. His already delicate wife, Polly, became a chronic depressive who remained a near-recluse for most of their long life together. The loss of several children in their early childhood added to her suffering. When at home, Marshall was devoted to Polly, and her long, letterless silences when they were apart grieved him, but there is no evidence that he seriously considered resigning from the court to be with her.

The work of the Marshall court appropriately forms the core of Mr. Paul’s book. His elucidation of its decisions—over 1,100, more than half of them written by Marshall—is refreshingly crisp and unhobbled by jargon. Although a lifelong Federalist, Marshall served his entire term during administrations controlled by Republicans, many of whom saw him as an enemy of their values. Even so, writes Mr. Paul, he “forged a consensus on nearly every issue by sheer personality and intellect.”

Marshall, says Mr. Paul, “was in all things a pragmatist.” Consistently rejecting a narrow interpretation of the Constitution, he asserted that it must respond flexibly to the nation’s needs. “In an era without precedent,” Mr. Paul writes, “Marshall invented the legal principles that form the foundation of American constitutional and international law today.” His skills included a remarkable ability to win agreement among his fellow justices. Over his 34-year tenure, all but 87 of the court’s decisions were unanimous, which helped endow them with an enduring authority that they would not otherwise have had.

Among the first of the Marshall court’s decisions was Marbury v. Madison. It was, writes Mr. Paul, “the single most significant constitutional decision issued by any court in American history.”

William Marbury was one of 42 justices of the peace for the District of Columbia who had been hastily approved by the Senate at the end of Adams’s term. Their commissions, though signed by Adams, hadn’t been officially delivered when the clock ran out on the administration. Jefferson directed his new secretary of state, James Madison, to deliver just 25 of them. Marbury, one of the 17 left behind, sued for his job.

When Marshall agreed to hear Marbury’s case, the Republican-controlled Congress charged that the court was carrying out a “daring attack” on the president himself. In reprisal, Congress eliminated the offices of 16 newly appointed circuit judges and canceled the Supreme Court’s 1802 term. The country’s first battle over the independence of the judiciary was under way: If Congress could fire judges, Mr. Paul says, all the constitutional limits on government would be thrown into question.

When the court finally met in February 1803, Marbury’s lawyer argued that his client’s appointment was known to have been approved by the Senate and that the administration was bound to recognize it. But both Jefferson and Madison refused to acknowledge the court’s jurisdiction and made it clear that they would not comply if ordered to install him. Here Marshall showed his genius for both legal reasoning and pragmatic compromise.

Marshall asserted that once Marbury’s commission had been signed, neither the president nor his secretary of state had any legal right to deny it. At this point, he might have bluntly ordered Madison to give Marbury his job. But his reasoning now took a surprising turn. He wrote that while the Judiciary Act of 1789 had expressly given the court the power to issue such an order, the Constitution had not done so. Thus the pertinent section of the Judiciary Act was unconstitutional and must be struck down. Marbury was still out of a job, but Marshall had deftly avoided a confrontation while setting a precedent for the court—one that would establish the principle of judicial review and elevate the court to its now unquestioned role as the ultimate arbiter of the Constitution.

Four years later, Marshall presided over another landmark case of comparable importance: the trial of former Vice President Aaron Burr for allegedly conspiring against the United States. The case involved payoffs, forged documents, false testimony and shockingly prejudicial actions by Thomas Jefferson, who loathed Burr as a schemer and rival.

That Burr had engaged in some kind of scheme is widely accepted. The details remain murky, but it appears he hoped to raise an army to invade Spanish territory beyond the border of the Louisiana Purchase. But there was no evidence that he had levied war against the United States. Marshall faced yet another daunting collision with the president. Burr’s lawyers demanded that Jefferson himself be forced to testify. Marshall declined to allow this, but he did order the president to turn over his correspondence with the shady Gen. James Wilkinson, a one-time Burr ally. Jefferson refused, declaring that the president’s correspondence was protected by “executive privilege.” ( Richard Nixon’s lawyers would cite the case in their initial refusal to turn over the Watergate tapes.)

Lacking evidence, the prosecutors argued that statements critical of the administration could be construed as treason—an argument that, Marshall recognized, if upheld, could be easily deployed to censor any American’s speech. In the end, he threw out virtually all of the government’s case. Republicans condemned Marshall, with one Richmond newspaper declaring that an independent judiciary “is a very pernicious thing.” Mr. Paul writes that Marshall’s decision “did more to secure free expression and prevent tyranny than any other court in our history.”

Many of the Marshall court’s decisions bore on economic matters. In one, an 1815 case wonderfully titled Thirty Hogsheads of Sugar v. Boyle—it had to do with casks of sugar exported on a British ship that was captured by an American cruiser—Marshall crafted a unanimous consensus in favor of the principle that international law is an inherent part of United States law. In 1824, in “the Great Steamboat Case,” he penned a decision that, in Mr. Paul’s words, “made it possible to forge a unified modern national economy” out of competing state policies. The case pitted the state of New York, which declared the right to license steamboats in state waters, against the young Cornelius Vanderbilt, who was trying to start a steam service across the Hudson River. The court vigorously asserted the federal government’s right to control interstate commerce, trumping state regulations.

Over the next quarter-century, the court unfurled a sequence of decisions that emphasized the supremacy of federal law, reflecting Marshall’s unbending belief that the Constitution was intended to “restrain or annul the sovereignty of the states” and providing a legal framework for the rejection of states-rights ideology. In 1821, he wrote in Cohens v. Virginia that state laws, “so far as they are repugnant to the constitution and laws of the United States,” were “absolutely void.” He consistently held that the Constitution was not a compact of the states but a creation of the people as such, undermining the premise that would soon gain force in the South: that states could nullify federal law.

Increasingly, Southerners saw Marshall as a traitor to their interests. As Mr. Paul notes, “states rights” was never just an abstract principle; it bore directly on the hard political matter of slavery. Even the “Great Steamboat” decision was seen as a threat to the “peculiar institution.” If Congress were given broad authority to regulate commerce, declared Virginia Rep. John Randolph, “they may emancipate every slave in the United States.”

There is no evidence that Marshall foresaw, much less desired, such an outcome. He was no fire-breathing apologist for slavery, but he was no abolitionist either. He owned several slaves and freed none of them. Although he “was not shy about inventing legal principles,” as Mr. Paul puts it, he invented none that threatened slavery.

By contrast, in one of the Marshall court’s last decisions, Worcester v. Georgia, in 1832, he came down courageously on the side of the beleaguered Cherokee Indians, who were on the brink of being forced off their land by the state of Georgia. But the decision was delivered still-born. President Andrew Jackson, whose agents were to enforce the ruling, simply ignored it, telling the Cherokees that “as certain as the sun shines to guide you in your path, so certain it is that you cannot drive back the laws of Georgia.”

The muscular federalism of the early republic died with Marshall, who succumbed to a spinal injury in 1835, at age 79. “Marshall saw with cold clarity that he had become irrelevant in the age of Jackson,” writes Mr. Paul. “His time had passed.” Jackson replaced him with Roger Taney, who would ratify every states-rights claim that came before the court until his own demise during the Civil War. Taney is little remembered today, except as a bulwark of reactionary jurisprudence. Marshall, however, is justly celebrated as the most far-sighted justice ever to lead the Supreme Court. His lasting achievements are ably served by Mr. Paul’s deeply felt and penetrating biography.

—Mr. Bordewich’s most recent book is “The First Congress: How James Madison, George Washington, and a Group of Extraordinary Men Invented the Government.”