The case, which will be tried before a judge in Santa Fe, stems from a lawsuit filed by New Mexico Attorney General Raul Torrez, a Democrat, accusing the social media giant of designing its products to addict young users and failing to protect children from sexual exploitation on its platforms.
At the heart of the trial is whether Meta's platforms have created a "public nuisance" under New Mexico law.
That finding would allow the judge to order wide-ranging remedies aimed at curbing alleged harms to young users.
The case is being closely watched as states, municipalities and school districts across the country pursue similar claims seeking to force changes at the industry level.
Monday's trial marks the second phase of New Mexico's lawsuit. A jury in March found Meta violated the state's consumer protection law by misrepresenting the safety of Facebook and Instagram for young users. It ordered the company to pay $375 million in damages.
Torrez's office is expected to seek both billions of dollars more in damages and an order requiring Meta to make substantial changes to its platforms for New Mexico users, according to court filings.
Meta has said it has already addressed many of the state's concerns and taken extensive measures to ensure its young users are safe.
The company said in court filings last week that many of the changes Torrez's office is seeking are impossible for it to comply with and may force it to withdraw from the state entirely.
"The New Mexico Attorney General's focus on a single platform is a misguided strategy that ignores the hundreds of other apps teens use daily," a Meta spokesperson said in a statement ahead of the trial.
"Rather than providing comprehensive protections, the state's proposed mandates infringe on parental rights and stifle free expression for all New Mexicans."
New Mexico's case is among a growing number of lawsuits accusing Meta and other social media companies of intentionally designing products to be addictive to young people.
New Mexico said it plans to ask the judge to order Meta to make changes including verifying users' ages, redesigning its algorithm to promote quality content for minors, and ending autoplay and infinite scrolling for minors.
