The first-degree murder charge out of Kern County on Tuesday comes after authorities recently charged Tubbs in connection to a 2019 robbery.
The suspect is being held on $1 million bond and is set to appear in court for an arraignment hearing on Tuesday afternoon, according to Kern County documents.
No further information about the murder charge was available as of Tuesday morning.
Tubbs became the center of controversy earlier this year after pleading guilty to a 2014 assault on a young girl inside a Denny's restaurant bathroom when the then-suspect was just weeks from turning 18. Prosecutors said Tubbs grabbed the girl by the throat, locked her in a stall, and put her hand down the girl’s pants.
Tubbs pleaded guilty to the attack last month, though the incident took place when Tubbs was two weeks shy of 18 and identified as a male named James Edward Tubbs. When authorities arrested Tubbs roughly eight years after the crime, the suspect, who has since been convicted of child molestation, began identifying as a woman, according to prosecutors.
Prosecutors sentenced Tubbs to two years at a juvenile facility because Gascon’s office declined to transfer the case to adult court, adhering to one of the progressive prosecutor’s day-one directives barring "children" from being tried as adults. The convicted criminal could, however, still serve as little as six months under California law and may not be required to register as a sex offender.
"Tubbs had a very lengthy criminal record before George Gascón allowed Tubbs to be sentenced to minimal time in a juvenile facility, which included arrests and convictions for murder, robbery, assault with a deadly weapon, domestic violence and even a prior sexual assault of a 4-yr-old girl," Los Angeles Deputy District Attorney Jon Hatami told Fox News Digital.
A spokesman for District Attorney George Gascon's office previously told Fox News that Los Angeles officials will be notified if Tubbs is released from custody in Kern County.
"District Attorney George Gascón is committed to protecting the public and especially our children. In this case, Hannah Tubbs continues to serve her Los Angeles County sentence, while being prosecuted on an unrelated robbery charge in Kern County," Ricardo Santiago, a public information officer for the DAs office said. "Her transfer was based on a 2019 warrant and approved by a court."
The case has sparked criticism of District Attorney George Gascon's directive that minor offenders suspected of committing serious crimes not be tried as adults as the DA faces a recall effort. Following the Tubbs sentence, Los Angeles County Supervisor Kathryn Barger called the outcome "unsatisfactory."
"Judge Barrera’s hands were tied today – due to the fact that the DA’s office failed to file a motion to transfer Tubbs to adult criminal court, which is where she rightly belongs," Barger said. "Instead, we’re left with a 26-year-old individual sentenced to two years in a juvenile facility in isolation, separated by sight and sound from the other juveniles."
Tubbs was later caught on a jailhouse phone call gloating about the case and bragging about not having to register as a sex offender.
"George shouldn’t have needed jail calls to convince him Tubbs was dangerous to our children. George has completely failed us all. He doesn’t deserve to be the LADA," Hatami said.
Tubbs was also accused of sexually molesting a 4-year-old girl at a California library in August 2013 while her mother was browsing books "just a few aisles over."
The inmate is currently being held under the name James Tubbs in Kern County.
Fox News' Michael Ruiz contributed to this report.