An official manual for undercover Immigration and Customs Enforcement officers obtained by VICE News show they have broad discretion to carry out searches without a warrant and to participate in illegal activity, like human trafficking or transporting drugs outside of U.S. borders.

The document, leaked to Unicorn Riot, a media collective that has obtained and published four other ICE manuals, dates back to 2008, but it was in use as recently as 2016, according to a senior official at the Department of Homeland Security, which confirmed the authenticity of the manual to VICE News.

ICE is now using a newer version of the training manual, but the document offers a glimpse into the tactics ICE undercover agents have used in the past and are likely using today to infiltrate organizations that bring undocumented immigrants into the U.S.

The senior official who confirmed the authenticity of the documents said they are typically password-protected and only accessible by ICE agents. The official did not know if there had been substantive changes to procedures since 2016. The person also said this was just one chapter in a larger handbook. Another former special agent who worked at ICE from 2008 to 2014 told VICE News that the manual’s style and content was consistent with others he’d seen previously.

Once undercover, the document also grants ICE officers “general authority” to engage in a wide range of “otherwise illegal activity,” including human trafficking, transporting drugs outside the U.S., and spying, “even if it is a crime under local or state law.”

“Approval of an undercover investigation or operation utilizing the appropriate procedures described in this handbook shall constitute authorization to participate in certain otherwise illegal activity that is considered a crime under federal, state, or local law,” the manual states.

Undercover officers are allowed to participate in activities such as hiding or transporting undocumented immigrants as long as the officer “does not have substantial control or direction of the scheme.” If an officer wants to get involved with that, the manual recommends they contact the Human Smuggling and Trafficking Unit for policy and procedures.

The manual also allows ICE officers to transport “drugs or other contraband” so long as it doesn’t enter the United States.

The manual offers several possible justifications for participating in illegal activity. For example, obtaining information or evidence would not be possible without engaging in said illegal activity. Or, doing something illegal is necessary to “establish or maintain credibility of a cover identity," or if someone is at risk of being killed or seriously injured.

If any of the authorized illegal activities results in violence, the undercover officer has to report what happened as soon as possible to the supervisor, and that information is meant to travel up to the chain of command, all the way to the ICE assistant secretary.

The release of this manual comes as ICE’s tactics are under intense public scrutiny. Earlier this month, undercover ICE officers pretending to be health inspectors arrested 114 undocumented immigrants at a garden store in Ohio after luring them with three boxes of Dunkin Donuts, on suspicion of being in the U.S. unlawfully.

ICE deputy press secretary Sarah Rodriguez declined to comment on the document or verify its authenticity. “We’re not going to comment on leaked documents, or training and tactical enforcement procedures that are considered law-enforcement sensitive,” she wrote in an email to VICE News.

Gregory M. Vecchi, assistant professor of criminal justice at Missouri Western State University and retired FBI agent of 29 years, said that the FBI was known for being a lot more conservative, compared to, say, ICE or the Drug Enforcement Administration, when it came to approving requests for undercover operations.

“The Bureau has very strict policies on undercover,” said Vecchi. Those strict policies are a direct result of the Abscam sting operation in the late 1970s and early 1980s that led to the convictions of seven members of Congress. “Since the FBI are the only ones who can investigate members of Congress, they put tight controls on the FBI in terms of authority and permission levels needed to do any type of undercover work,” Vecchi added.

Like ICE, Vecchi says that the FBI can get permission to engage in illegal activity, which could include posing as a human trafficker or a drug dealer.

“Certain cases lend themselves to undercover work,” said Vecchi. “Organized crime cases, or instances where people are dealing illegal contraband.”

The ICE manual, meanwhile, states clearly that their undercover policy is designed to “allow extreme field flexibility and discretion.”

The federal government is allowed to seize money that undercover ICE agents encounter during their investigations, including money laundering schemes or human trafficking.

The handbook specifies that ICE officers are not allowed to commit murder, rape, robbery or aggravated assault in relation to an undercover investigation.

The manual says that its constitutionally permissible for law enforcement officers to conduct criminal investigations without revealing their official status.

Where it gets murky, according to the manual, is when it comes how much undercover officers can search, whether they can seize or copy evidence, and whether they can secretly record conversations.

The manual says that an undercover officer can “legally enter a suspect’s premises if that operative has the suspect’s consent, whether expressed or implied.” The officer can collect evidence which is “voluntarily revealed by the suspect,” which includes anything in plain view.

What the undercover officer can search and for how long is relative to the level of consent given by the suspect. The manual says, for example, if the undercover officer was a houseguest, “it would be reasonable to have access to the closet in the room where he or she was to sleep.”