[2] In August 2013, a report by Reuters revealed that the Special Operations Division (SOD) of the U.S. Drug Enforcement Administration advises DEA agents to practice parallel construction when creating criminal cases against Americans that are based on NSA warrantless surveillance.
[3] Two senior DEA officials explained that the reason parallel construction is used is to protect sources (such as undercover agents or informants) or methods in an investigation.
An example from one official about how parallel construction tips work is being told by Special Operations Division that: "Be at a certain truck stop at a certain time and look for a certain vehicle."
DEA would alert state troopers and they may wait for that certain vehicle and decide to use drug searching dogs to see if there is any illegal drug-related activity.
[citation needed] Parallel construction in this case in the US usually is the result of tips from the DEA, as well as the Special Operations Division that are derived from sources within foreign governments, intelligence agencies or court-authorized domestic phone recordings.