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.

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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.

Former President Trump courted Black voters in Detroit Saturday, when he raised President Biden's authorship of the 1994 crime bill, which remains a sore point after three decades.

Headlining a roundtable discussion at the predominantly Black 180 Church as his campaign was announcing the launch of a Black voter coalition, Trump noted that rising crime rates hurt his audience's community the most.

"Look, the crime is most rampant right here and in African American communities," Trump said Saturday in Detroit. "More people see me, and they say, ‘Sir, we want protection. We want police to protect us. We don’t want to get robbed and mugged and beat up or killed because we want to walk across the street to buy a loaf of bread.’"

Trump took aim at Biden and the Biden-Harris campaign during his remarks, recalling how Biden, as a senator in 1994, authored the Violent Crime Control and Law Enforcement Act, which Biden has since called a "mistake." 

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"Biden wrote the devastating 1994 crime bill, talking about ‘super predators.’ That was Biden. You know, he walks around now talking about the Black vote. He’s the king of the ‘super predators,’" Trump said during the event. 

Biden authored the Senate’s version of the bill when he served as a senator from Delaware. Signed into law by President Clinton, the bill has been blamed for mass incarceration that disproportionately affected the Black community. 

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The bill’s passage came on the heels of the crack cocaine epidemic that throttled Black communities in the 1980s and early 1990s.

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Biden had a long history of authoring legislation viewed at the time as tough on crime but now seen as controversial and contributing to the spike in America's incarceration rates. 

As the consumption of crack cocaine spiraled in the 1980s, for example, Biden co-sponsored another bill that soon became controversial, the Anti-Drug Abuse Act of 1986. That legislation, which was signed into law by President Reagan, established harsher sentencing penalties for possession of crack cocaine than the drug's powder form. Crack cocaine and cocaine have a similar chemical makeup, but Black Americans disproportionately used crack cocaine compared to their White counterparts, leading to an outcry that the bill unfairly targeted Black Americans. 

Biden has since distanced himself from the 1986 and 1994 legislation, saying of the 1986 drug bill that "the road to hell is paved with good intentions," The Washington Post reported in 2019. He added ahead of the 2020 election that the 1994 crime bill was a "mistake" due to its effect on the Black community. 

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Trump in his comments suggested Biden referred to criminals in the 1990s as "super predators." Biden did refer to criminals in that era as "predators" who were "beyond the pale," but the specific phrase "super predators" was not used by Biden. 

Instead, first lady Hillary Clinton used the phrase in 1996 while speaking favorably of the legislation signed into law by her husband in 1994 and has since apologized for the phrase. 

​​"Just as in a previous generation, we had an organized effort against the mob. We need to take these people on," she said at the time. "They are often connected to big drug cartels; they are not just gangs of kids anymore. They are often the kinds of kids that are called super predators. No conscience, no empathy. We can talk about why they ended up that way, but first we have to bring them to heel."

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Amid Clinton’s failed bid for the White House against Trump in 2016, a Black Lives Matter activist confronted her about the phrase, prompting the former secretary of state to walk back the comment. 

"Looking back, I shouldn’t have used those words, and I wouldn’t use them today," Clinton told The Washington Post in 2016. 

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Trump’s pitch to Black voters in Detroit comes as polling indicates Trump is gaining popularity among the voting bloc. Last month on CNN, a data analyst appeared stunned as the network explained Trump's support among Black voters more than doubled to 22% compared to 2020, while Biden saw a 12% drop. Overall, Biden still holds a strong lead over Trump among Black voters. 

Biden won Michigan by three points in the 2020 election, but recent New York Times polling conducted in six battleground states last month found Trump leading in a handful of key states, including Michigan, Pennsylvania, Arizona, Georgia and Nevada. The poll, published last month, found Biden holds more favorability in one battleground state — Wisconsin. 

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Following the roundtable discussion, the Biden-Harris campaign hit back that the 45th president's audience at the church was "noticeably empty and white" and that his "eleventh hour" outreach to Black voters "isn't fooling anyone." 

"Donald Trump thinks the fact that he has ‘many Black friends’ excuses an entire lifetime of denigrating and disrespecting Black Americans, but Black voters know better — and Trump’s eleventh hour attempt at Black ‘outreach’ isn’t fooling anyone," Biden-Harris 2024 Director of Black Media Jasmine Harris said in a press release. 

"Black voters haven’t forgotten that this man entered public life calling for the death penalty for the innocent Central Park 5 and entered political life spreading racist conspiracy theories about Barack Obama. We haven’t forgotten that Black unemployment and uninsured rates skyrocketed when Trump was in the White House. And we sure haven’t forgotten Trump repeatedly cozying up to white supremacists and demonizing Black communities to his political benefit — because that’s exactly what he’ll do if he wins a second term. Black voters sent Joe Biden and Kamala Harris to the White House in 2020, and they’re ready to make Donald Trump a two-time loser in 2024." 

Trump’s newly-formed Black coalition, Black Americans for Trump, was launched just days ahead of Juneteenth, which commemorates the end to slavery in the U.S. and is celebrated June 19 each year. 

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"Never has it been more clear that Joe Biden’s reckless reversal of President Trump’s America First policies is the very reason why Black communities have been utterly decimated under his Administration with sky-high grocery and gas prices, untenable housing costs, an invasion of illegal migrants and rampant violent crime," Team Trump Senior Advisor Lynne Patton said in a statement in the campaign’s press release. 

"On day one, Donald Trump will reinstate all his proven policies on immigration, law and order, energy and the economy and put Black America First." 

Trump was joined by Black leaders and supporters during the roundtable discussion Saturday, including former Secretary of Housing and Urban Development Ben Carson, Republican Michigan Rep. John James and former Detroit Police Chief James Craig. 

The pastor of 180 Church, Lorenzo Sewell, joined "Fox & Friends First" Friday ahead of the roundtable, lauding Trump’s visit as one that "means so much" to the community.

"Sometimes we forget about the Black vote. Sometimes we forget about the power of what it means to vote for those who are in office and, in urban America, our voice matters. That's why it means so much to us that the former president will come and value our voice," Sewell said.