The deadly shooting in El Paso is being treated as a "domestic terrorism" case, prosecutors there said. And the FBI said it has opened a "domestic terrorism" investigation into the July shooting at the garlic festival in Gilroy, California.

But the individuals who commit these violent acts will ultimately be indicted on different federal charges — hate crimes or weapons possession. Here's why: Domestic terrorism is defined in the U.S. legal code but it is not codified as a law that can be prosecuted.

"It's confusing to the public to call someone a domestic terrorist but not charge them with a crime of terrorism," said Mary McCord, a former Department of Justice official who served as acting assistant attorney general for national security from 2016 to 2017. 

How is domestic terrorism defined?

The FBI defines domestic terrorism as acts "perpetrated by individuals and/or groups inspired by or associated with primarily U.S.-based movements that espouse extremist ideologies of a political, religious, social, racial, or environmental nature."

The USA Patriot Act from 2001 defines domestic terrorism as a dangerous act occurring within U.S. territory that violates criminal laws in ways that are "intended to intimidate or coerce a civilian population; influence the policy of a government by intimidation or coercion; affect the conduct of a government by mass destruction, assassination or kidnapping." That definition is also in the U.S. Government Code, the 53 title compilation of federal legal statutes.  

According to McCord, domestic terrorism was first defined in the federal code in 1992. Prior to that period, McCord is doubtful domestic terrorism was even a part the public consciousness or law enforcement radar. "I don't think people back then were even using that verbiage. We didn't even have internal terrorism at that time," she said.  

How does "terrorism" differ from "domestic terrorism"? 

Acts of terrorism that "transcend national boundaries" are federal crimes. The U.S. Code of laws lists several violent crimes under the umbrella of terrorism that can be prosecuted if committed against persons within the U.S. 

In a 2008 speech to the Anti-Defamation League, Jonathan Solomon, special agent in charge of the FBI's Miami, Florida division, explained this difference: 

"What makes domestic terrorism different is that domestic terrorists are based or operate solely in the U.S., and their acts target the U.S. government or U.S. citizens," Solomon said. "They can be 'right-wing' or 'left-wing' extremists, such as white supremacists, anti-government militias, or anarchists. They can be 'single-issue' groups, such as animal rights or environmental rights extremists. And they can be 'lone wolves' with their own agendas. Think of Unabomber Ted Kaczynski." 

Under the Patriot Act, the federal government has multiple resources to combat international terrorism. It has the authority to conduct surveillance of suspected terrorists, and can mount undercover sting operations and obtain financial records. 

They have fewer tools to investigate domestic terrorism. 

According to a recent op-ed by McCord in the Washington Post, "these techniques, though, are limited when it comes to preventing domestic terrorist attacks. FBI guidelines forbid agents from deploying them solely on the basis of First Amendment-protected activity."  

The First Amendment protects free speech, including the right to openly espouse any ideology, even hateful ones. So domestic extremists have greater legal latitude to express their views.

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