The German government last year opted to share intelligence with U.S. agencies to protect against national security threats so long as the information wasn't used to carry out drone attacks, German news magazine Der Spiegel reports.
A German national was reportedly among those killed last month in Pakistan when missiles were fired allegedly from a U.S.-operated drone.
The strike reportedly targeted at least 12 suspected Taliban fighters in the area.
Drone strikes have occurred more frequently during U.S. President Barack Obama's tenure, though the issue is controversial in Pakistan because the two countries aren't at war.
The German national, given a pseudonym by the Der Speigel, was allegedly tied to the Islamic Movement of Uzbekistan, which is listed as a terrorist organization by the United States.
His mother, also protected by an alias, said the German government should investigate the case as murder.
Der Speigel notes that, despite the legal ambiguity, at least 800 drones are operating in Pakistani skies.