But while we found Dr. Ford’s allegations credible during a 10-month investigation, Ms. Ramirez’s story could be more fully corroborated. During his Senate testimony, Mr. Kavanaugh said that if the incident Ms. Ramirez described had occurred, it would have been “the talk of campus.” Our reporting suggests that it was.

[Read answers to reader questions on this essay.]

At least seven people, including Ms. Ramirez’s mother, heard about the Yale incident long before Mr. Kavanaugh was a federal judge. Two of those people were classmates who learned of it just days after the party occurred, suggesting that it was discussed among students at the time.

We also uncovered a previously unreported story about Mr. Kavanaugh in his freshman year that echoes Ms. Ramirez’s allegation. A classmate, Max Stier, saw Mr. Kavanaugh with his pants down at a different drunken dorm party, where friends pushed his penis into the hand of a female student. Mr. Stier, who runs a nonprofit organization in Washington, notified senators and the F.B.I. about this account, but the F.B.I. did not investigate and Mr. Stier has declined to discuss it publicly. We corroborated the story with two officials who have communicated with Mr. Stier; the female student declined to be interviewed and friends say she does not recall the episode.

Mr. Kavanaugh did not speak to us because we could not agree on terms for an interview. But he has denied Dr. Ford’s and Ms. Ramirez’s allegations, and declined to answer our questions about Mr. Stier’s account.

Yale in the 1980s was in the early stages of integrating more minority students into its historically privileged white male population. The college had admitted its first black student in the 1850s, but by Ms. Ramirez’s time there, people of color comprised less than a fifth of the student body. Women, who had been admitted for the first time in 1969, were still relative newcomers.

Mr. Kavanaugh fit the more traditional Yale mold. His father was a trade association executive, his mother a prosecutor and later a judge. They lived in tiny Bethesda, Md., and owned a second home on Maryland’s Eastern Shore. As a student at a prominent Jesuit all-boys school, Georgetown Prep, Mr. Kavanaugh was surrounded by the sons of powerful Washington professionals and politicians. He was an avid sports fan and known to attend an annual teenage bacchanal called “Beach Week,” where the hookups and drinking were more important than the sand and swimming.

Ms. Ramirez grew up in a split-level ranch house in working-class Shelton, Conn., perhaps best known for producing the Wiffle ball, and didn’t drink before college. Her father, who is Puerto Rican, rose through the Southern New England Telephone Company, having started as a cable splicer. Her mother, who is French, was a medical technician.