BATON ROUGE — Starting Aug. 1, it will be illegal to use a cell phone while driving in Louisiana except for hands-free calls or navigational purposes.

The policy was signed into law Monday by Gov. Jeff Landry.

The law, which passed the legislature as HB 519, prohibits mobile device use, except for voice calls on hands-free systems like smartwatches and looking at navigation, given the device is not in a driver's hands.

Rep. Brian Glorioso's legislation says that sending and reading text messages, emails and social media posts are now finable offenses.

The law outlines specific instances where the restrictions would not apply, including reporting a traffic, criminal or medical emergency and communicating as a "transportation network company driver" or emergency official.

The restrictions do not apply while a vehicle is stationary, the legislation's text reads.

Breaking the new law is punishable by a $250 fine if the violation happens in a school zone or a highway construction zone, and $100 everywhere else. If a person is involved in a crash at the time of the violation, the fine will be doubled, the law notes.