A creative commons license is a kind of copyright license that gives people the right to use, share, and expand upon a creator’s work whether this is an art work, a piece of literature, or a scientific or academic material. It offers a significant protection against accusations of copyright infringement and is believed by some to offer artists a degree of flexibility they may desire. It is also in the interest of citizens to see that the artwork they pay for through government funding for the Arts is made available for their benefit in some fashion. Mandating creative commons licensing for all state-funded artwork would accomplish that goal.
The benefits of government-funded university research are not shared widely enough in society, with universities retaining full ownership, for the most part, of their academic work. This means they get to profit from the government-funded research, and rarely have to share it with the taxpayers. By mandating that the research it spends so much taxpayer money on enter the public sphere, the government can more effectively spread the benefits of its own largesse and do its duty to all its citizens to provide them with the full benefit of what it produces with their tax money.