General Services Administration officials involved in a lavish $800,000 Las Vegas conference are expected to speak out about the controversial gathering for the first time Monday before a House committee investigating it.

The House Oversight Committee hearing, the first on the spending scandal, will also look to the culture at the agency to "make sure this doesn't happen again," Chairman Darrell Issa, R-California, said.

"What often happens is, an (inspector general) does their job, perhaps some people are held accountable, but the culture doesn't change," Issa said. It must be clear that there is "zero tolerance for this" and that the culture will be changed, he said.