President Biden has signed into law a bipartisan missing persons bill, backed by Gabby Petito’s parents and the family of missing Connecticut man William Smolinski Jr., who vanished in 2004.

The Help Find the Missing Act, introduced in September by Democratic Connecticut Sens. Chris Murphy and Richard Blumenthal and Republican Sens. John Cornyn of Texas, John Hooven of North Dakota and Thom Tillis of North Carolina, is also known as "Billy’s Law" for Smolinski.

It aims to streamline the national process for reporting missing persons and dramatically expand a federal law enforcement database.

"Amazing," Petito’s father, Joseph Petito, tweeted Thursday. "Thank you @ChrisMurphyCT @RepJahanaHayes, @Jim_Schmidt416, @TaraPetito @Nikischmidt927, all the members of congress, and the senate for this. #NamUs #TogetherWeCan #missingPersons."

GABBY PETITO'S FAMILY ANNOUNCES NEW BILL TO HELP FIND MISSING PERSONS: 'A HUGE STEP FORWARD'

Gabby Petito poses in front of a winged mural

Gabby Petito was reported missing in September 2021, roughly two weeks after her former fiancé Brian Laundrie is believed to have killed her and abandoned her body at a campsite in Wyoming. (@petitojoseph/Instagram )

The legislation offers funding to the National Missing Persons and Unidentified Persons System (NamUs) for a missing persons/unidentified database that the public can access and contribute to; connects NamUs with the FBI’s National Crime Information Center (NCIC) to improve missing persons databases; requires law enforcement to report missing persons to NamUs; establishes incentives to help states report missing persons; and requires the Justice Department to issue best-practice guidelines regarding the handling of missing persons cases.

"This is a big deal that is going to ensure the thousands of other families with missing loved ones won’t face the same obstacles going forward," Murphy said in a statement.

Cornyn praised the bill’s bipartisan support and vowed that it would help law enforcement bring justice to the friends and families of missing persons.

"For families who have exhausted all possible leads to find their loved one, improving the missing persons reporting process is essential," he said.

BIDEN SIGNS BIPARTISAN COLD CASE LAW ESTABLISHING FEDERAL RIGHT TO REQUEST REVIEW FOR VICTIMS' FAMILIES

Petito and Schmidt families

Gabby Petito's parents and stepparents during an Oct. 7, 2021, interview regarding the then-active search for Brian Laundrie, who is suspected of killing their daughter in Wyoming before returning to his parents' house in Florida and killing himself in a swamp nearby. (Fox News)

The new law will also require police to collect exemplars, such as DNA, dental records and other details, and upload them to the newly connected NamUs and NCIC databases — while it provides departments with federal funding to do so.

"The key takeaway is that when police go and collect the data… and upload this in there, I think we’re going to see hits pop up from all over the country," said Joseph Giacalone, an adjunct professor at John Jay College of Criminal Justice and a retired NYPD sergeant.

Under the previous system, he said, there was no guarantee that evidence discovered in one state would register as a match in a missing person case on the other side of the country.

Gabby Petito at Bryce Canyon

Gabby Petito poses for an Instagram photo in Bryce Canyon National Park. (Family of Gabby Petito)

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The new law, along with the Homicide Victims’ Families Rights Act that Biden signed in August, will help police crack cold cases around the country, Giacalone told Fox News Digital.

"For family members, I think, of not only cold case homicides but now missing persons, the last couple of months… provide a lot of hope for closure," he said.

Fox News’ Audrey Conklin contributed to this report.