This week, a 14-year-old made headlines for her epic takedown of a popular theory put forth by University of Illinois history professor Richard Jensen, Ben Collins reports for The Daily Beast.

The historical business practice of posting “Help Wanted! No Irish Need Apply” signs in windows and newspaper want ads to deter Irish workers has become part of America's cultural history and a powerful symbol of the discrimination faced by Irish immigrants at the turn of the last century. But for decades, Jensen has suggested that it was more myth than fact.

Here’s how Jensen’s argument goes: the signs were actually extremely rare and perhaps nonexistent, and the myth of the signs persists due to a popular song entitled “No Irish Need Apply.”

Jensen received backlash when he first published his theory, and the debate flared up again this March with the publication of numerous think pieces about St. Patrick's Day. One of those articles made it into the hands of eighth-grader Rebecca Fried, who turned to Google for more information.

To her surprise, she got results. The Washington Post's Moriah Balingkit reports that newspaper archive databases turned up dozens of work ads from the 1800s with the “No Irish Need Apply” caveat spanning a number of professions and U.S. states. According to Fried's findings, which were published last month in the Journal of Social History, the New York Sun newspaper ran 15 “No Irish Need Apply” ads in 1842 alone.

Driven more by curiosity than by academic fervor, Fried poked holes in the theory with a few calculated keystrokes. Jensen quickly responded to her work, arguing that the teen misinterpreted the data and that the signs were still quite rare. When Casey Egan at Irish Central first reported the story, the two went back and forth in the article's comments.

Though the debate about "No Irish Need Apply" signs may still be raging in the comments section, Fried’s work proves that the signs and the discrimination they represented did indeed exist — and that anyone with a curious mind and a nose for research can challenge the historical status quo.