Murderer Pregnant At the Time of Her Crime Gave Birth in Prison

Oxygen The mugshot of Giselle Esteban, convicted murderer of nursing student Michelle Le

On Friday, July 10, Dateline NBC is rebroadcasting an episode called “Vanished,” which examined the disappearance and murder of Vietnamese-American nursing student Michelle Le in 2011. Ahead of that episode, here’s what you need to know about the crime, the woman who was convicted of the murder, and how she gave birth in prison.

Giselle Diwag Esteban Was Pregnant When She Murdered Michelle Le and Gave Birth in Prison

On May 27, 2011, Michelle Le, a nursing student at the Kaiser Permanente Medical Center in the San Francisco area, was training with her co-workers when she ran out to the parking structure to get something from her car and never returned. According to United Press International, Le’s locked car was later found three blocks from the hospital with bloodstains inside. Authorities said at the time that security footage from the parking garage and her cellphone records indicated she was killed by someone she knew.

A city-wide search began shortly after Le’s disappearance, but an arrest was made in the case before Le’s body was found.

On September 7, Giselle Diwag Esteban was arrested for Le’s murder. The two were former friends and Le’s DNA was found on one of Esteban’s shoes during a May 29 search of Esteban’s home, according to the San Jose Mercury News. Cellphone records also showed that Le and Esteban’s phones traveled a similar route immediately after Le disappeared, with transmissions coming from the Niles Canyon and Sunol Canyon areas.

Esteban was indicted on a murder charge in December 2011. The San Jose Mercury News reported that grand jury transcripts released after the indictment showed that Esteban left increasingly hostile, profane, and threatening messages in the months before Le was killed. Esteban also sent messages to Scott Marasigan, the father of her unborn child, and with whom she suspected Le was having an affair.

“No matter how many times Marasigan denied an affair, Esteban refused to believe him,” Prosecutor Butch Ford said in the transcript. “And she became fixated.”

He also said that Esteban became “so enraged” about this affair she thought was happening that she “began essentially to hunt down Michelle.”

Marasigan testified that he and Le had dated for a few weeks several years ago, but that they never had a sexual relationship.

Ford said that Esteban “attacked [Le] in the parking lot, threw her body into her own car, drove to a makeshift grave, and buried her body.”

Esteban and Marasigan already had a daughter together but at the time of Le’s disappearance and murder, they were on-again, off-again. According to the Bay City News (via Patch), Marasigan testified during the trial that Esteban became mad at him when he was awarded custody of their daughter in 2010 and moved her to the San Francisco area.

Esteban maintained that Marasigan was the father of her second child, but Marasigan testified that he knew of at least one other person who could have been the father. Esteban gave birth to a healthy baby boy shortly before Thanksgiving while in custody, reported the San Francisco Gate.

In December 2012, Esteban was convicted of first-degree murder and sentenced to 25 years in prison. At the time, Judge Jon Rolefson said he had never seen more condemning circumstantial evidence pointing to a killer than what the police and prosecutors had on Esteban, according to the San Francisco Gate. Rolefson also said he hadn’t “seen or heard any hint of remorse” from Esteban, according to the San Francisco Gate.

Le’s Remains Were Found Four Months After Her Disappearance

After the cellphone transmissions pointed investigators to the Niles Canyon and Sunol Canyon areas, authorities were able to narrow their search for Le. On September 17, Le’s body was found in a shallow grave in the Sunol-Pleasanton canyon area.

An exact cause of death was never determined, however. There was a “dinner-plate-sized pool” of Le’s blood found in the parking garage along with some of Le’s hair. Her blood was also found inside of her car and her DNA was found in a stain on Esteban’s shoe. Esteban’s DNA was also found on the steering wheel and turn signal of Le’s car.

“You can tell from the evidence presented that (cause of death) may never be determined,” Ford told jurors. “But that’s not required to prove that somebody died.”

Dateline airs Fridays and Saturdays on NBC.

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