The new year brings a host of new laws across the country that go into effect starting Sunday — from restrictions on holding a cell phone while driving to greater freedom for carrying a gun in public.

While many states already restrict the use of cell phones in the car, California is now taking that precaution a step further. As of Sunday, it's illegal for drivers to hold their phones behind the wheel. The devices must be mounted and can be used only for functions that require a single tap or swipe, like answering a call.

"If you're not paying attention and something happens in front of you, by the time your mind thinks about it and you react to it, it is definitely too late," says Officer Jesus Chavez of the California Highway Patrol.

Meanwhile, Philadelphia becomes the first major American city with a tax on sugary sodas — one and a half cents an ounce. That's 24 cents for a 16-ounce drink. The industry is challenging the law in court.

"The people who can least afford to pay it will be the ones that are paying a higher proportion of it," says Susan Nelly of the American Beverage Association.

Berkeley, California, was the first city to impose such a sugar tax, adopting it in 2015. When Michael Bloomberg was New York's mayor, he attempted to have a similar tax imposed by the board of health, but a court said only New York's city council had that power.

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And beginning on Sunday in Missouri, anyone 19 or older who owns a gun can carry it in public, concealed, without getting training or a permit. Sheriff Mike Sharp of Jackson County was among law enforcement officials who opposed the idea.

"This law would allow anybody to go get a gun, carry it, and never have to fire the weapon until they think it's necessary to use it, without any education whatsoever," he said.

But a sponsor of the new law, State Senator Brian Munzlinger, discounted fears of more gun violence. "The basis of this whole bill is that it allows law-abiding citizens to protect themselves and their families," he said.

California, by contrast, imposes tougher gun laws as of the first day of 2017. It's now illegal to sell most AR-15 style rifles with removable magazines, or ammunition clips, banned as assault weapons. Current owners must register them.

Under a new law in Maine, doctors cannot prescribe more than a seven-day supply of such painkillers Vicodin or Percocet, or a 30-day supply for chronic pain. The measure is intended to reduce opioid abuse.

In Colorado, it's now a crime to misrepresent a pet as a service animal. The state says untrained pets interfere with real service dogs. Angela Easton, a service dog trainer, says pet owners often ask for an accessory allowing them to take their dogs almost anywhere.

"We get calls from people who want a service dog vest so that they could keep their dog with them all the time."

Starting today in Illinois, bicycles have the same right of way as cars. The law was passed after a Vietnam veteran, Dennis Jurs, was killed when a driver failed to yield.

Drivers in Boston begin the new year with a lower speed limit — 25 miles an hour, down from 30, imposed to reduce traffic deaths.

And in Alabama as of Jan 1., there will be no more common law marriages. Getting married to celebrate the New Year will require a license and a ceremony, even one as simple as saying "I do" in the county courthouse.