A former FBI special agent gave an inside look into how federal and state law enforcement apprehended the El Salvador migrant suspect in the multi-state homicide investigation of Rachel Morin.
Retired FBI Supervisory Special Agent Scott Duffey told Fox News Digital that, at the beginning of any homicide investigation, law enforcement starts with those closest to the victim.
"First and foremost, you start with loved ones, whether it be a spouse, a partner or a romantic partner," he said. "And then once you exclude them, then you move outward."
Duffey, who met with Morin's family in Harford County, Maryland, after her murder, said the FBI's Combined DNA Index System (CODIS) allowed law enforcement across state lines to stay on the same page as the 10-month investigation progressed.
CODIS is a database used by federal and state law enforcement to compile DNA profiles of convicted offenders, unsolved crime scene evidence and missing persons.
A break in Morin's homicide case came after a piece of DNA evidence showed up thousands of miles from Morin's Maryland hometown in Los Angeles weeks after her disappearance.
"And lo and behold, the two DNA matches from DNA from Rachel Morin's crime scene and the DNA from LA were a match through CODIS," he said.
Morin said the CODIS operates under "strict guidelines," which gave him comfort about the legitimacy of the DNA match.
"They have very strict guidelines, and the fact that you had two DNA matches was very comforting to me as a former investigator," he said.
The former special agent said the unexpected twist came after investigators discovered Morin's suspected killer, later identified as Victor Martinez Hernandez, an illegal El Salvador migrant, was not a U.S. national.
Martinez Hernandez's immigration status prompted law enforcement to rely on FBI international offices, called legal attachés.
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"What's their next stop out of the country into El Salvador?" Duffey said. "Now, it's one thing when you have a genealogical tree, and you're able to say, 'OK, we're getting closer' and the DNA experts are able to say, ‘Hey, this is a match’.
"But when you go out of the country, you lose certain ownership of an investigation."
The FBI international office in El Salvador was used to "bridge that gap" with law enforcement in the U.S. on Morin's case," Duffey said.
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"But having an FBI office in El Salvador, they're able to bridge that gap with American law enforcement and with El Salvadorian authorities," he said.
El Salvador authorities then communicated with U.S. law enforcement that Martinez Hernandez had fled his country of origin after brutally killing someone in the Central American country.
The news prompted the FBI to put out a "red notice," which told all law enforcement involved in Interpol to be on the lookout for Martinez Hernandez.
"That red notice would have alerted authorities, ‘Do not let this individual go any further. Stop and detain,'" Duffey said. "All those things are falling into place, not to mention the hard work that Harford County investigators pursued with LA authorities."
Duffey said he believes law enforcement used Martinez Hernandez's "digital forensics footprint" to piece together the final touches on its investigation.
"A cell phone, an email address, something that this individual is communicating with anybody else and thereby having such a footprint that law enforcement can zone in, pinpoint to a relatively small, very tight area to where surveillance could go out and investigate," he said.
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Duffey said it was "amazing" Martinez Hernandez, a wanted fugitive, managed to evade capture for 10 months after Morin's homicide.
"It will be interesting to see what his means were," he said. "Who was supporting this individual who was already a fugitive from justice from his country of origin?"
RACHEL MORIN MURDER
On Saturday, Harford County Sheriff Jeffrey Gahler announced the arrest of Martinez Hernandez.
Gahler said the 23-year-old was arrested in Tulsa, Oklahoma, and charged with first-degree murder and first-degree rape.
The 23-year-old migrant illegally crossed into the United States in February 2023, police announced.
"We all suspected that Rachel was not his first victim," Gahler said. "It is my understanding that this suspect, this monster, fled to the United States illegally after committing the brutal murder of a young woman in El Salvador a month earlier, in January of 2023."
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Gahler said a first DNA match for Martinez Hernandez was from a Los Angeles attack in March 2023.
"Once in our country, and likely emboldened by his anonymity, he brutally attacked a 9-year-old girl and her mother during a home invasion in March of 2023 in Los Angeles," Gahler said. "And as everyone I believe is aware, that was our first DNA match linking Rachel's case to the one in Los Angeles."
Morin, 37, was reported missing in August by her boyfriend, who said she never returned after going out for a run on the Ma & Pa Trail, a pedestrian trail in Bel Air, a quiet and typically safe town about 28 miles northeast of Baltimore, Aug. 5, 2023.
Her body was found on a trail the next day.
