Leland Ford, representative of Santa Monica called for a Congressional investigation into the event stating:
"...none of the explanations so far offered removed the episode from the category of 'complete mystification' ... this was either a practice raid, or a raid to throw a scare into 2,000,000 people, or a mistaken identity raid, or a raid to lay a political foundation to take away Southern California's war industries."
Secretary Stenson offered two theories to the War Department. One being that they were commercial planes flown by the enemy and launched from secret fields in California or Mexico. Or they were small planes launched from Japanese submarines.
Either way, Stinson speculated the whole incident was to learn the location of anti-aircraft defenses or to deliver a blow to civilian morale.
The next day, even though several reports of downed craft were reported, the city had sustained damage from the 1,440 rounds of anti-aircraft ammunition to its buildings as well as a few deaths. No downed crafts were ever found....according to the military.