A teen was charged with murder after a 12-year-old girl died from a fentanyl overdose. A legal expert said that kind of charge is rare because it's hard to prove.

• A California teenager was arrested and charged with the murder of a 12-year-old girl who died of a fentanyl overdose.
• Prosecutors say that a 16-year-old sold a fentanyl-laced pill to the girl and she died shortly after ingesting it.

A California teenager was arrested and charged with the murder of a 12-year-old girl who died of a fentanyl overdose allegedly caused by the pill they sold, California prosecutors announced.

And a legal expert told Insider that a murder charge like this "doesn't happen often" because cases like this are typically "hard to prove unless you have direct evidence."

The Santa Clara District Attorney's office said that the 16-year-old suspect from San Jose — whose identity was not released — was arrested on Tuesday in connection with the 2020 death of the young girl, who was not publicly named.

Prosecutors say that the 16-year-old sold a fentanyl-laced pill to the girl and she died shortly after ingesting three-quarters of it, making her the youngest person to fatally overdose in the county in 2020.

The 12-year-old was with two other teens when she contacted the suspected drug dealer and purchased the "M-30" pill on November 14, 2020, according to prosecutors.

The group videoed the victim lining up the crushed pill before she snorted it, prosecutors said. Following her consumption of the pill, the child passed out and began snoring — "a telltale sign of a fentanyl overdose," the district attorney's office said.

The 12-year-old was brought to a hospital in San Jose where she was pronounced dead.

"After thousands of deaths, everyone should know that fentanyl is a deadly poison," District Attorney Jeff Rosen said in a statement.

According to the district attorney's office, authorities discovered screenshots in the alleged dealer's Google Photos account showing public service warnings about fentanyl overdoses from before the girl's death.

As the teen suspect's name hasn't been released, it is unclear if they have hired an attorney in the case. The district attorney's office did not immediately respond to a request for comment.

The arrest of the minor — who faces prison time — marks only the second time that the Santa Clara DA's office charged an accused drug dealer with murder after a fatal overdose.

A San Jose man is currently facing a murder charge after selling a fatal opioid over Snapchat to a Santa Clara 18-year-old in 2020, the DA's office said.

The Los Angeles Times reported last year that Southern California district attorneys were joining in on a growing national crackdown on fentanyl dealers by pushing for murder charges for overdose deaths.

Dmitriy Shakhnevich, a professor at New York's John Jay College of Criminal Justice, told Insider that drug dealers have been hit with murder charges in connection with overdose deaths in the past, but it is rare.

"It may be more common now, but it's happened before and it doesn't happen often," Shakhnevich said.

Cases like this, Shakhnevich said, are "hard to prove unless you have direct evidence to show that the person dealing the drugs knew of some risk and knew that that risk was on some level foreseeable…and ignored that risk."

"There must have been some degree of culpability," said Shakhnevich, who is also a defense attorney.

He added, "Dealing drugs won't get you there unless there was something that indicated that you should have known of some potential risk of death. You can make that jump surely, but it would be tough."

The potency of the drug itself "will absolutely matter" in a case, Shakhnevich said, noting, "If it was marijuana, it would be different."

Fentanyl is a factor in more than half of overdose deaths in the US, according to the National Center for Drug Abuse Statistics.

The synthetic opioid, which the US Drug Enforcement Administration says is 80 to 100 times more potent than morphine, resulted in the deaths of approximately 42,700 people in 2020, the National Center for Drug Abuse Statistics said.

More than 150 people die every day from overdoses related to synthetic opioids like fentanyl, according to the Centers for Disease Control and Prevention.

Fentanyl, according to the CDC, is "a major contributor to fatal and nonfatal overdoses in the US."