The graduate student at the center of a scandal over a newly retracted study that has shaken trust in the conduct of social science apologized for lying about aspects of the study, including who paid for it and its methodology, but he said Friday in his first interview since the scandal broke that he stands by its finding that gay canvassers can influence voters’ attitudes on same-sex marriage.

The student, Michael J. LaCour, a doctoral candidate in political science at the University of California, Los Angeles, said the attack on his study — which was retracted Thursday by the journal Science — amounted to an academic ambush. “It’s completely unprecedented in the way it was done,” he said, referring to an account of the case posted by two colleagues last week, questioning his work. “They never contacted me directly, there was no transparency, and as a grad student I don’t have the same protection as a professor.”

Mr. LaCour disputes one of the main charges against him: that he improperly erased his raw data. That was one of the charges that led his co-author, Donald P. Green, a widely respected political scientist at Columbia University, to ask the journal to retract the study last week. The destruction of the data was not improper, he said, but in fact was required by U.C.L.A.’s institutional guidelines to protect study participants.

Image A photo of Michael J. LaCour from his Facebook page. A study Mr. LaCour co-authored was retracted by the journal Science on Thursday.

“At the end of the day, I was the one responsible for the raw data, and if something were to happen and reporters tracked people down, that’s a lawsuit,” he said.