Both Merkel and her conservative Interior Minister Wolfgang Schaüble have recently called for the change to improve the ability of elite German police force the GSG-9 to work with the country's military when attempting to free the captives of pirates operating off the coast of Somalia.
But Merkel's junior coalition partner the centre-left Social Democrats (SPD) don't consider a constitutional amendment necessary.
“It is completely unproblematic according to state and international law that the German armed forces fight the pirates and free hostages,” Dieter Wiefelspütz, the SPD's parliamentary security policy spokesman, told daily newspaper Handelsblatt on Monday. “I don't know why we need to change the Basic Law.”
Wiefelspütz said further that the SPD will not allow any changes to the constitution in the run-up to the election this September.
The debate stems from the abandoned rescue of the hijacked container ship Hansa Stavanger earlier this month, which included a partially German crew. After being stationed on the USS Boxer, the GSG-9 was recalled after the mission was deemed too risky.
Schäuble told Bild newspaper on Sunday that Germany's ability to respond to such situations abroad was hampered by the fact German law only provided for the police to undertake hostage rescues and not the military. “But that's really a job for the Bundeswehr,” he said. “For that though we'll have to change the legal foundation with a constitutional amendment.”