JOHN YANG: Louisiana police have a new way of using DNA to track down criminal suspects.

As Stephanie Sy reports, police say it's a boon for solving cold cases.

But civil liberties advocates say they're worried about privacy.

STEPHANIE SY: Once a person is arrested, police can swab their cheek and within 90 minutes the machine can determine if that person is connected to other crimes anywhere in the country.

Police say it's already quickly solving cold cases.

But privacy advocates worry about its growth and potential for improper use.

Our community's correspondent Roby Chavez has been looking into how Louisiana came to be the national leader in this rapid DNA technology.

Robbie, it's good to see you.

So how does this new tool work?

ROBY CHAVEZ: Well, look, the rapid DNA machine does the work of crime labs in a fraction of the amount of time in less than two hours.

There's no human interaction with a DNA sample, once it is loaded into the machine.

And the sample doesn't have to be sent off to a lab for technicians to examine.

It's all done right there in the police station by police officers.

It's very compact, and comes about the size of a desktop computer.

But it does come with a hefty price about $250,000 for each machine, and each sample can cause about $150.

But that price tag should help police identify a suspect a lot faster and lessen the likelihood that people want it for other crimes will be released.

It's also expected to cut down on the backlogs that are slowing down crime labs.

STEPHANIE SY: So Roby, how effective has it been at solving crime since this technology has been put into use?

And is the state expected to adopt this technology widely?

ROBY CHAVEZ: Yes, well, look, Louisiana has been using that technology since August.

It's already outperformed expectations.

Recently it's solved a crime and some 500 miles away in Georgia.

It also helped solve a police shooting which remained unsolved for the last two years.

The state does hope to have four of these machines fully operational across the state by the end of the year, including in big cities like here in New Orleans and Baton Rouge.

STEPHANIE SY: What are the privacy implications and other concerns that have been brought up with this technology?

And is this the kind of thing that can hold up in a court of law?

ROBY CHAVEZ: Well, look, Stephanie, In the past, the U.S. Supreme Court has said that DNA collection is a legitimate police booking procedure.

Even so there is some backlash largely over how technology could be misused.

Rapid DNA came online fairly quickly after Congress approved a rapid DNA program in 2017, which led to the first two month pilot program in Louisiana, Florida, Arizona and Texas.

Louisiana is now the only state authorized to continue using the rapid DNA program.

Critics also warned that the rollout comes without adequate oversight.

The Electronic Frontier Foundation, a nonprofit focused on digital privacy concerns, warns that there are a few protections for Americans right now, when it comes to DNA collection.

And rapid DNA encourages the growth of government databases.

The ACLU warns there are already racial disparities in DNA collection, which could be made worse by the practice.

For its part, the FBI says there are strict standards and protocols in place.

In fact, they can impose fines on police agencies, if they find that they're misusing this technology.

In addition, there are two audits that are required by law each year.

That has to be conducted by the FBI as well as the Louisiana State Police.

STEPNANIE SY: Is this something that you hear a lot of other states are interested in in obtaining other police departments interested in having this tool at their disposal?

ROBY CHAVEZ: Well, look, the FBI says that they can scale up at any time.

The big problem is the cost.

It does cost a lot of money and a lot of states don't have the technology infrastructure in place on top of that the laws are a problem, only about 20 states outlined here in blue currently allowed DNA to be collected at the time of booking.

Even still, many of these laws differ when a sample can be taken.

Most states seen in red here do not allow DNA collection until there is probable cause or not at all, which makes them poor candidates for the FBI program.

Now, I should mention that there are other rapid DNA machines that are marketed and used by police agencies across the country for various uses, including examining data collected from crime scenes examining DNA collected at crime scenes.

The FBI warns that this technology at crime scenes is not fully developed, and there are several improvements that are necessary.

In the meantime, privacy advocates say that if the government curtail some of the funding, it would slow the growth of these DNA databases.

STEPHANIE SY: Certainly something to keep our eyes on our communities correspondent out of New Orleans, Roby Chavez, thank you for your reporting.

ROBY CHAVEZ: You're welcome.