At NSGL, the enlisted African Americans who tested in the top 30 to 40% were selected for non-labor battalion assignments. Port Chicago was manned by workers drawn from those remaining. The Navy determined that the quality of African American petty officers at Port Chicago suffered because of the absence of high-scoring black men, and that overall levels of competence were further reduced by the occasional requirement for Port Chicago to supply drafts of men with clear records for transfer to other stations. The Navy's General Classification Test (GCT) results for the enlisted men at Port Chicago averaged 31, putting them in the lowest twelfth of the Navy. Officers at Port Chicago considered the enlisted men unreliable, emotional, and lacking the capacity to understand or remember orders or instructions.