GEOFF BENNETT: Your old plastic driver's license could soon be getting a digital upgrade.

Digital reporter Tim McPhillips walks us through three things you should know, including some of the benefits and some of the concerns.

TIM MCPHILLIPS: One, what's a mobile driver's license?

IAN GROSSMAN, American Association of Motor Vehicle Administrators: It's essentially what it sounds like, which is taking your driver's license and making it a digital credential that you can carry on your smartphone, your watch, your tablet.

TIM MCPHILLIPS: That's Ian Grossman, president and CEO of the American Association of Motor Vehicle Administrators.

They're a trade organization that provides DMVs with best practice guidance, as well as software and tech infrastructure.

Twenty states and Puerto Rico offer a form of a digital driver's license.

Some allow you to add it directly to your mobile wallet, like your credit card.

Others have a state-created mobile app that stores your I.D.

Two, what are the benefits?

Well, the idea is, when you need to show your I.D., you could essentially tap your phone on a reader, like at an airport or a doctor's office, or while getting a speeding ticket.

IAN GROSSMAN: You would never hand over your phone.

TIM MCPHILLIPS: And that could help to limit the information you share.

Take, for example, a liquor store.

IAN GROSSMAN: They don't need to know your name.

They don't need to know your address.

TIM MCPHILLIPS: And if, like me, you have lost your wallet and/or left it in a TSA bin, it's more difficult for someone to get into your phone than it is to just pick up your plastic I.D.

IAN GROSSMAN: What you have time to do is get to any browser anywhere, log into your online DMV account and say, I have lost that device, pull that credential off of that phone.

TIM MCPHILLIPS: But there are concerns around this new technology to prove who we are.

And that brings us to three, government data collection.

Here's American Civil Liberties Union senior policy analyst Jay Stanley.

JAY STANLEY, Senior Policy Analyst, American Civil Liberties Union: One problem is that the standard for digital I.D.

that a lot of the states, although not all of them, are adopting would actually let the government track you.

TIM MCPHILLIPS: So what does that mean?

Well, when you tap your mobile I.D.

on a reader, information about you is sent from point A to point B. That simple transaction involves major decisions.

Like, does verification happen locally on your phone or on a server?

And could a third entity like a state or federal government access data on where you used your I.D.?

Stanley and the ACLU have rallied against that last scenario called phone home or server retrieval over potential abuses.

For AAMVA's part, Grossman says states that might allow server retrieval would be blocked from using AAMVA's digital I.D.

systems.

IAN GROSSMAN: We have prohibited the ability to what we would say call back to the agency.

TIM MCPHILLIPS: All this is pressuring states not to build systems that phone home.

But because it is possible to do with the technology and laws in place today, the responsibility falls on our elected officials not to flip the switch.

But: JAY STANLEY: We have seen a couple states that have put in place some very good protections in their laws.

TIM MCPHILLIPS: In March, Utah put in place the nation's first digital identity bill of rights that bans phone home architecture.

Stanley agrees that states need to be proactive in codifying a phone home ban into law.

JAY STANLEY: The states are sleepwalking into building a version that's not privacy-protective, and we're going to get stuck with that as a standard for potentially generations.

TIM MCPHILLIPS: As of now, some state governments on both sides of the aisle have allowed mobile driver's licenses, but others have rejected them, like Texas and Minnesota.

But Grossman says widespread adoption is coming.

IAN GROSSMAN: But nobody is forcing anybody to do it.

TIM MCPHILLIPS: And Stanley argues that too should be codified in law.

JAY STANLEY: You should have a right to continue to use your plastic license.

TIM MCPHILLIPS: His fear?

JAY STANLEY: But it has a real potential that we're going to wake up one day, we're all going to be forced to get these things.

They're going to become like a virtual ankle bracelet.

TIM MCPHILLIPS: For PBS News, I'm Tim McPhillips.

GEOFF BENNETT: And you can find more on this online, including live election results from state primaries later this evening.