Indeed, one of the main reasons Tarbell and McClure picked Standard as a target was the mass of documentation on the company accumulated over the years by various investigations: government reports, court records, and transcript testimony, including from Rockefeller himself. And “History of Standard Oil” just bludgeons you with facts—charts, graphs, court records, tables, you name it.

Third was their towering journalistic ambition. The muckrakers steered directly toward the biggest, hardest problems (e.g. political corruption, industrial consolidation) and the most powerful institutions (Standard Oil) and the most powerful people (Rockefeller).

Fourth, and aligned with the third, the muckrakers recognized the importance of agency. Moralists that they were, they understood that great economic events, like great financial events, are not natural phenomena, something that just happens, but instead are the result of the decisions made by individuals, people, and that powerful individuals had more influence than those with less power. Muckraking at its best was an early (and effective) attempt to hold powerful people and institutions to account.

The epigraph to Tarbell’s History is a quote from Emerson: “An institution is the lengthened shadow of one man.”

Finally, McClure and the muckrakers, after a fashion and without intending to, crafted what can be called a journalism ideology of sorts, an ideology of anti-corruption, a keystone value of American journalism to this day. McClure might call it, anti-“lawlessness.”

The January 1903 issue of McClure’s is considered a landmark because it has three classic muckraking articles by Tarbell, Baker, and Steffens. McClure himself realized only at the last minute what he had in the issue, and hurriedly wrote an editorial to explain what it all meant.

“We did not plan it so,” he wrote. “[I]t is a coincidence that the January McClure’s is such an arraignment of American character as should make everyone one of us stop and think,” he wrote. “Capitalists, workingmen, politicians, citizens all breaking the law or letting it be broken. Who is left to uphold it?”

In an appeal to what was then a developing idea of a public interest, he answered his own question: “There is no one left. None but all of us.”

It is worth noting that Tarbell never condemned Standard for its size, only for lawless acts—chiefly colluding with railroads to drive competitors out of business. She had no trouble acknowledging the genuine achievements of Rockefeller and his cohorts and devoted an article to “The Legitimate Greatness of the Standard Oil Company.”

It was the very fact that it could have succeeded without resorting to illegal acts that so exasperated Tarbell. As she says in her memoir, “I never had an animus against their size and wealth, never objected to their corporate form. I was willing that they should combine and grow as big and rich as they could, but only by legitimate means. But they had never played fair, and that ruined their greatness for me.”

The historian Richard Hofstadter wrote a memorable passage explaining the muckrakers’ immense popularity. It was their willingness “not merely to name the malpractices in American business and politics but to name the malpractitioners and their specific misdeeds and to proclaim them to the entire country.” Because of the muckrakers, “It now became possible for any literate citizen to know what barkeepers, district attorneys, ward-heelers, prostitutes, police court magistrates, reporters and corporate lawyers had always come to know in the course of their business.”

In my book, I’m going to discuss how muckraking qualities and values were incorporated into mainstream media, including, by the way, business news, after WWII via the work people of like Clark Mollenhoff, who investigated Teamster corruption in the 50s and 60s, Bob Greene, and the rise of a period of neo-muckraking in the 1970s and the spread of what can be called the investigative reporting movement. In the mid-70s muckrakers even got their own trade group, Investigative Reporters and Editors. I’ll argue that the muckraker’s principles, for various reasons, were abandoned during the mortgage era.

Dean Starkman Dean Starkman runs The Audit, CJR's business section, and is the author of The Watchdog That Didn't Bark: The Financial Crisis and the Disappearance of Investigative Journalism (Columbia University Press, January 2014). Follow Dean on Twitter: @deanstarkman.