NASHVILLE, Tenn. — A bill that increases penalties for Tennessee school bus drivers caught using portable electronic devices at the wheel has been signed into law.

Gov. Bill Haslam approved the legislation on Thursday. It passed the Tennessee House and Senate with nearly unanimous votes.

As previously reported, the bill was spurred by the fatal crash of two school buses in Knoxville in December 2014. In that crash, which killed two students and an aide, investigators found that school bus driver James Davenport had been sending and receiving text messages.

“Following the events of December 2014, I vowed to do everything within my power to make sure that nothing like this happened in Tennessee again,” said Charme Allen, Knox County’s district attorney general. “Thanks to a statewide effort, Tennessee now has the strongest law in the nation when it comes to distracted school bus drivers.”

Under previous law in Tennessee, a school bus driver who uses a mobile phone while transporting students would be charged with a Class C misdemeanor, which is punishable by a $50 fine.

The newly passed law, which goes into effect July 1, makes the offense a Class A misdemeanor for school bus drivers. That carries a minimum sentence of 30 days in jail, a fine of at least $1,000, and permanent prohibition from operating a school bus in the state.

The legislation also broadens the list of devices that school bus drivers are banned from using while driving. In addition to mobile phones, a few examples are laptop computers, pagers, cameras, and electronic games.

The bill specifies that school bus drivers can’t use the prohibited portable electronic devices while loading or unloading students, in addition to while the bus is in motion and transporting students.

Communications with dispatch via two-way radios, or other devices used in a similar way as two-way radio communications, are still allowed, as are phone calls in emergencies.

Allen, the Knox County attorney general, worked with bill sponsors Sen. Becky Duncan Massey and Rep. Eddie Smith over the past several months to support the passage of the legislation.

“With child safety in mind, we have dramatically broadened and strengthened the law to ensure that our school bus drivers are keeping their focus where it should be," Massey said.

“This was a vital step to protect our children from unnecessary danger on their way to and from school,” Smith added. “The strengthened penalties should make it very clear that the safety of our children is our number one priority.”