06 November 2026

25 Years Later: Revisiting NGSQ’s Jefferson-Hemings Special Issue

 


By Andre Kearns

The Smithsonian has reconstructed much of Thomas Jefferson’s genome from a lock of hair and compared his DNA with descendants of Sally Hemings. The results add remarkable new genetic evidence supporting a conclusion historians and genealogists had already reached: Thomas Jefferson fathered children with Sally Hemings.

Twenty-five years ago, the National Genealogical Society Quarterly (NGSQ) devoted its September 2001 issue to the Jefferson Hemings question. Today, the National Genealogical Society (NGS) is pleased to make that special issue freely available to the public. It is an opportunity to revisit an important chapter in American history and demonstrate the timeless value of rigorous genealogical scholarship.

What Genealogists Concluded 25 Years Ago

The centerpiece of the issue was Helen F. M. Leary’s “Sally Hemings’s Children: A Genealogical Analysis of the Evidence.” Leary approached the controversy as a genealogist, asking a straightforward research question: Who was the father of Sally Hemings’s children?

The DNA available in 2001 could not answer that question by itself. A landmark 1998 study established that Sally’s son Eston carried the Jefferson Y chromosome, but it could not distinguish Thomas Jefferson from other Jefferson males. 

So Leary did what genealogists do when no single piece of evidence provides the answer: she assembled and correlated all available evidence. She considered DNA alongside Jefferson’s records, the timing of Sally Hemings’s pregnancies, contemporary accounts, Madison Hemings’s identification of Jefferson as his father, Jefferson’s treatment of Sally’s children, and evidence concerning alternative fathers.

One finding was especially significant. Every known conception after Sally returned from France coincided with Thomas Jefferson’s presence at Monticello, and none occurred during his absences. 

After weighing the evidence, Leary concluded, “The sum of the evidence points inescapably to Thomas Jefferson as father of all seven of Sally Hemings’s children.” She also acknowledged a fundamental principle of good genealogy: conclusions may need to be revisited when significant new evidence emerges. Twenty-five years later, new DNA evidence has emerged, and it strengthens that conclusion.

Why This Issue Still Matters

The special issue extends well beyond Leary’s landmark article. Thomas W. Jones put the opposing Scholars Commission report to the test against the Genealogical Proof Standard. His conclusion: it fell short. Historian Joshua D. Rothman examined how assumptions about Jefferson’s character influenced historians’ treatment of the evidence. Gary B. Mills addressed a question central to African American genealogy: How can we establish parentage in families shaped by slavery when no single record explicitly identifies a father? 

That last question resonates deeply with me because much of my own research focuses on African American families and people who were enslaved, including my own. This work often requires us to reconstruct relationships that were never formally recorded; take oral history seriously while testing it against other evidence; and connect records created by institutions that often had little interest in preserving Black family relationships.

The Genealogical Proof Standard provides a framework for doing that work responsibly through exhaustive research, accurate source citations, analysis and correlation, appropriate use of negative evidence, resolution of conflicting evidence, and a soundly reasoned conclusion. 

It would be tempting to tell today’s Smithsonian story as one about DNA finally solving a historical mystery, but that misses the larger lesson. DNA is evidence, just as records and oral histories are evidence. Rarely does one source tell the entire story.

The tools available to family historians have changed dramatically since 2001, but the principles underlying good genealogy have not. New technology can give us new evidence. Rigorous genealogy gives us the framework to understand what that evidence means.

Twenty-five years later, this special issue demonstrates the enduring value of both NGSQ scholarship and the Genealogical Proof Standard. By making it freely available today, NGS hopes to introduce a new generation of genealogists to scholarship that shows what our field does at its best: form focused research hypotheses, follow the evidence, test competing explanations, and build conclusions that can stand the test of time. We invite you to read the issue and discover what it can still teach us.

Access the NGSQ 2001 Special Issue: Jefferson-Hemings