BETHESDA, Md. — Fifty years after the Warren Commission concluded that a lone gunman killed President John F. Kennedy, a conference examining the assassination convened here, dominated by skeptics who mulled over conspiracy theories and cast doubt on official reports.
One panelist, John Newman, who gave a presentation on CIA pseudonyms used by agents connected with the Kennedys, said the Warren Report “was not just wrong. The longer we have to study the case, the wronger its conclusions become.”
Theories about the case have sprouted from the moment that Kennedy was killed, and countless forums have been held since then. This gathering, five decades after the Warren Commission published its report on Sept. 24, 1964, drew more than 200 people.
It was sponsored by a private group, the Assassination Archives and Research Center, which says on its website that it is the world’s largest private archive “dedicated to acquiring, preserving, and disseminating information on political assassinations.”
One of the speakers, Antonio Veciana, an 86-year-old involved in the anti-Castro movement, said through a translator that he had seen a CIA officer in Dallas with Lee Harvey Oswald before Kennedy’s assassination. Attendees had so many questions for Veciana that his talk went almost an hour over the allotted time.
One attendee, Mike Chesser of Arkansas, who was 8 years old at the time of the assassination, said he wanted to learn more about what he believes is “our true history.”
“I always felt there were a lot of unanswered questions,” Chesser said.
The conference began Friday with panels on secrecy and democratic accountability and featured testimony from witnesses who said they encountered Oswald in the months before the assassination.
On Saturday, the conference will focus on the subsequent “coverup’’ of the assassination, and a dramatization of the Warren Commission will be presented Sunday.
The official investigation was overseen by then-Chief Justice Earl Warren. But in the half century since Warren Commission, public opinion polls consistently show that a majority of Americans do not believe its primary finding: that Oswald, a disgruntled former Marine, acted alone in murdering the 35th president.
A 2013 Gallup poll found 60 percent of Americans think others were involved, although that percentage was down from its peak in 1976, when 81 percent said they believed there was a conspiracy.
Theories about who the culprits might have been include leading organized crime figures, Cubans who were seeking to overthrow communist dictator Fidel Castro, Castro himself, and elements within the CIA, or some amalgam of these groups.
The attendees filled the ballroom of the Bethesda Hyatt Regency Hotel as a row of cameras filmed the scene for an upcoming DVD. Books written by the conference’s speakers, with titles such as “Oswald: Russian Episode,”' were sold in the lobby.
Jefferson Morley, a former Washington Post reporter who has researched the assassination, said he believed the Internet would usher in a new era of Kennedy assassination research.
“Now anybody, anywhere can get access to the original record of the assassination, or most of it,” Morley said. “That has never been true over the past 50 years and it’s only started to be true recently. It’s only going to become more true as time passes.”
Bryan Bender of the Globe staff contributed to this report.