* Verdict could affect thousands of similar cases against

tech companies

* Plaintiffs' focus on platform design may make liability

harder to avert for companies

* Mounting criticism over child safety shifts debate to

courts, state governments

By Dawn Chmielewski

LOS ANGELES, March 25 (Reuters) - A Los Angeles jury

reached a verdict on Wednesday in a landmark social media

addiction trial that involves Meta's Instagram and

Google's YouTube, according to spokespeople for the

plaintiff and Meta.

The jury is expected to read the verdict on Wednesday.

The outcome could influence thousands of similar cases against

the tech companies brought by parents, attorneys general and

school districts. At least half of American teens use YouTube or

Instagram daily, according to the Pew Research Center.

The Los Angeles case involves a 20-year-old woman who said she

became addicted to the apps at a young age because of their

attention-grabbing design. The plaintiffs in the Los Angeles

proceeding focused on platform design rather than content,

making it harder for the companies to avert liability.

Snap and TikTok were also defendants in the trial. Both settled

with the plaintiff before it began. Terms of the agreements were

not disclosed.

MOUNTING CRITICISM

Large technology companies in the U.S. have faced mounting

criticism in the last decade over child and teen safety. The

debate has now shifted to courts and state governments. The U.S.

Congress has declined to pass comprehensive legislation

regulating social media.

At least 20 states enacted laws last year on social media usage

and children, according to the nonpartisan National Conference

of State Legislatures, an organization that tracks state laws.

The legislation includes bills that regulate the use of

cellphones in schools and require users to verify their ages to

open a social media account. NetChoice, a trade association

backed by tech companies such as Meta and Google, is seeking to

invalidate age verification requirements in court.

A separate social media addiction case brought by several states

and school districts against technology companies is expected to

go to trial this summer in federal court in Oakland, California.

Another state trial is slated to begin in Los Angeles in

July, said Matthew Bergman, one of the attorneys leading the

cases for the plaintiffs. It will involve Instagram, YouTube,

TikTok and Snapchat.

Separately, a New Mexico jury on Tuesday found Meta violated

state law in a lawsuit brought by the state's attorney general,

who accused the company of misleading users about the safety of

Facebook, Instagram and WhatsApp and of enabling child sexual

exploitation on those platforms.