Three of the top presenters scheduled to speak at a technology conference in Texas next week will deliver their remarks remotely due to leak investigations that have left them all unable or unwilling to come to the United States.

Former intelligence contractor Edward Snowden will discuss the impact of the National Security Agency’s spy efforts at the South by Southwest Interactive Festival in Austin, Texas next Monday, organizers announced this week.

Planners for SXSW said on Tuesday that Snowden, the 30-year-old ex-systems analyst who leaked secret NSA documents to the media last year, will participate in a live discussion at the festival via teleconference from Russia. WikiLeaks founder Julian Assange and journalist Glenn Greenwald have both previously agreed to speak at this year’s event as well.

“Hear directly from Snowden about his beliefs on what the tech community can and must do to secure the private data of the billions of people who rely on the tools and services that we build,” festival organizers said in a statement.

Ben Wizner — the director of the American Civil Liberties Union’s Speech, Privacy and Technology Project and a legal advisor to Snowden — will moderate the conversation between Snowden and the ACLU’s chief technologist, Christopher Soghoian. The event will be broadcast online courtesy of the Texas Tribune.

Previously unpublished documents disclosed to the media by Snowden since last summer have exposed an array of NSA programs involving the United States spy agency’s efforts to acquire seemingly all digital communications across the world. He’s been accused of espionage and theft by the US Department of Justice for leaking that information, but the approval by Moscow last August of an asylum request there has allowed him to so far deter being prosecuted in America.

Assange, the founder of anti-secrecy group WikiLeaks who is also under investigation for disclosing classified documents, previously agreed to speak at the conference remotely for an event scheduled for this Saturday morning. The 42-year-old Australian publisher has been confined to the Ecuadorian Embassy in London for over a year, and cannot leave the facility without facing immediate arrest at the hands of British authorities. He’s wanted for questioning in Sweden.

On Monday, American journalist Glenn Greenwald will also speak about the ongoing NSA controversy at the festival, but from Brazil. He’s a confidant of Snowden and has worked closely with the former systems analyst on the NSA documents, but on advice of counsel has avoided returning to the US since the first stories involving the intelligence leaks were published last June.

"Surveillance and online privacy look to be one of the biggest topics of conversation at the 2014 SXSW Interactive Festival," reads a statement released this week by individuals involved in the event.. "As organizers, SXSW agrees that a healthy debate with regards to the limits of surveillance is vital to the future of the online ecosystem."