Democrats control both the Senate and Assembly but lack a two-thirds margin needed to pass tax increases. Incoming Assembly Speaker Marilyn Kirkpatrick, D-North Las Vegas, has said a discussion on Nevada's tax structure will begin early in the session, though Democrats have stopped short of advocating for new taxes.Republican Gov. Brian Sandoval, midway through his first term, has said he will oppose any new taxes. Assemblyman Pat Hickey, GOP minority leader, said Republicans welcome the tax discussion. "It's not impossible in this session or the next that there could be something that resulted in restructuring Nevada's tax system," the Reno Republican said. "But that doesn't necessarily mean it will only be done at the ballot box. "It should more appropriately be done by the Legislature and I think Republicans are certainly coming prepared to have that discussion." Senate Minority Leader Michael Roberson, R-Las Vegas, said he, too, welcomes the debate on "whether implementing an income tax helps attract new businesses and industries to Nevada, or whether it effectively shuts down such efforts." Personal income tax is banned in Nevada by the state Constitution, and Roberson likened the initiative to "income-based taxes on our citizens." Nevada also does not have a corporate income tax. "For that reason, I strongly oppose this income tax proposal," Roberson said.