House Intelligence ranking member Schiff speaks with reporters at the U.S. Capitol in Washington Thomson Reuters The ranking Democrat on the House Intelligence Committee released a statement Tuesday outlining the protocols surrounding incidental intelligence collection after former National Security Adviser Susan Rice reportedly "unmasked" US citizens in intelligence reports.

Rice reportedly tried to learn the identities of officials on President Donald Trump's transition team whose conversations with foreign officials may have been incidentally collected during routine intelligence-gathering operations. Typically, when Americans are swept up in foreign surveillance, they are referred to as something like "Person One," hiding their names. Revealing their identities is called "unmasking."

Rep. Adam Schiff defended the process of unmasking, saying that it's legal. The identities of US citizens swept up in incidental intelligence collection may be revealed if the person's name is needed to make sense of an intercept or a crime is involved in the conversation.

"When it is necessary to unmask a name to understand the significance of the communication, there is a process for doing so, which is also lawful," Schiff said in the statement. "Our committee routinely reviews whether our intelligence agencies are properly masking names and unmasking them as appropriate."

Sciff also said the incidental collection of intelligence that sometimes includes conversations with US citizens is "unavoidable" and "lawful."

Schiff explained that when the US is "doing lawful surveillance for the purpose of gathering foreign intelligence" and a surveillance target mentions a US citizen or business, that can constitute "incidental collection." This can also occur when a foreign party under surveillance calls or writes to a US citizen.

"Some incidental collection is unavoidable, and as long as proper procedures are being followed, it is fully lawful," Schiff said. "It does not constitute either wiretapping or surveillance of Americans."

Some Republicans — like Senate Intelligence Committee member Tom Cotton — were quick to condemn Rice. Cotton said it was "hard to imagine the circumstances [under which] you would" unmask a name in an intelligence report "in the ordinary course of business."

National-security experts have said that Rice's reported requests to identify who was speaking with the foreign officials before Trump was inaugurated were neither unusual nor against the law — especially if, as Eli Lake of Bloomberg reported, the foreign officials being monitored were discussing "valuable political information" that required the identity of the people they were speaking to, or about, to be uncovered.