Miami surgeon says slain girl suffered ‘destructive’ stab wounds ‘over and over’

Detectives said Martha Guzman was 11 years old when her mother's ex-boyfriend killed her in 2014 in Miami. (Courtesy photo)

MIAMI – Martha Guzman was 11 years old and home alone when a man she knew used a key her mom had kept hidden to enter the Miami apartment that she shared with her family and stab her, prosecutors said.

Miguel Ruiz Lobo used to be her mother’s live-in boyfriend. It had been about five months since he and her mother had broken up. Her mother’s requests for restraining orders had been denied.

Nearly nine years later, prosecutors are seeking the death penalty for Ruiz Lobo who is on trial for first-degree murder and occupied burglary. He appeared in court Wednesday before Miami-Dade Circuit Judge Marisa Tinkler Mendez, as the jury listened to the testimony of a crime scene technician, and Dr. Nicholas Namias, a trauma surgeon who saw Martha at Jackson Memorial Hospital’s Ryder Trauma Center.

“I just remember seeing this horrible — more than a stab wound on the left neck and wrist,” Namias said. “Suicide attempts with a knife are usually some clean single wound, not over and over or destructive.”

Ruiz Lobo’s defense claims he had absolutely nothing to do with the girl’s murder. Prosecutors say they have incriminating DNA evidence and surveillance video to show otherwise.

Detectives believe it took Ruiz Lobo about 30 minutes to kill Martha. Prosecutors played a video in court showing Ruiz Lobo arriving at the crime scene shortly before 10:30 a.m. and leaving at about 11 a.m. Investigators reported the DNA under Martha’s fingernails belonged to Ruiz Lobo, who had scratches on his face and arms.

Martha’s mother Amaury Alvarenga told the jury on Tuesday that she walked into her apartment on June 25, 2014, at 834 NW 4 St., in Miami’s Little Havana, to find her daughter curled up on the floor — with a knife sticking out of her neck and cuts on her wrists.

“She had three cuts in the neck and the knife stuck in her throat,” Alvarenga said in Spanish later adding, “I ripped it off her throat and tossed it aside ... Her eyes were all glued together with tears.”

Alvarenga also said that the decision to break up with Ruiz Lobo was related to his alcoholism and emotionally abusive behavior. During her opening statement, Miami-Dade Assistant State Attorney Laura Adams said Ruiz Lobo had blamed Martha for asking her mother to break up with him.

“This was personal,” Adams said.

Ruiz Lobo had cut Martha’s wrists in an attempt to fool others into thinking that she had committed suicide, but detectives didn’t buy it, Adams said.

Before the trial, the medical examiner reported the stabber had slashed her wrists so deep that the knife cut through her tendons, so she couldn’t have stabbed herself in the neck.

The witness testimony on Monday included Martha’s older sister Stefanie Rivera who said Ruiz Lobo had told her that he didn’t like her sister, and Officer Suney Lastra, a Miami police veteran, who said Martha was “somebody innocent who did not deserve this.”

The trial is scheduled to continue at 9 a.m., on April 10.

Ruiz Lobo has been in the custody of Miami-Dade Corrections and Rehabilitation since July 21, 2014, after a grand jury indicted him when he was 42 years old. Records show he marked his 51st birthday in March at the Metrowest Detention Center. If the jury finds him guilty, he could spend the rest of his life in prison.

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About the Authors:

Liane Morejon is an Emmy-winning reporter who joined the Local 10 News family in January 2010. Born and raised in Coral Gables, Liane has a unique perspective on covering news in her own backyard.

The Emmy Award-winning journalist joined the Local 10 News team in 2013. She wrote for the Miami Herald for more than 9 years and won a Green Eyeshade Award.