King Juan Carlos' future legal future status is uncertain.
While the outgoing monarch currently enjoys sovereign immunity from civil or criminal prosecution, Spain's constitution does not provide any special legal protection for Juan Carlos after he abdicates.
The Royal Palace is now concerned this could open the flood gates to a whole suite of legal proceedings against the king, the country's El Mundo reported on Friday.
"The reasonable course of action would be to offer protected status (aforamiento) to the king," a spokesperson for the palace said.
"It's common sense, to avoid ridiculous situations."
Spanish law offers a unique form of special protected status (aforamiento) to people including members of the royal family, MPs and certain public officials. This means they can only be tried in the country's very highest courts.
King Juan Carlos's abdication will be formalized after the country's parliament passes a law green-lighting the decision, a move expected to take within a few weeks.
However, this brief piece of legislation does not make mention of the monarch's future legal status.
But sources told El Mundo that the government was working flat out to find a solution to the legal black hole, and this could be approved even more quickly than the king's abdication.
The country's judges are generally in support of a move that will protect the king from endless legal disputes once his abdication has approved, Spanish daily 20 minutos reported.
What form this will take, however, remains to be seen.