Jurors deliberating the fate of six men being tried a second time for allegedly plotting to attack Chicago's Sears Tower asked in a note Tuesday whether swearing an oath to al-Qaida is a crime, an indication they are wrestling with a crucial piece of FBI videotape evidence. Defense lawyers insisted the answer should be no and prosecutors said the opposite. US District Judge Joan Lenard answered with her own note telling jurors to carefully read her instructions in the case, particularly those describing material support to a foreign terrorist organization. "This is a determination for them to make," Lenard said outside the jury's presence. "They may see it as providing material support or they may not." The men face up to 70 years in prison if convicted of all charges for allegedly plotting to start an anti-government war by toppling Chicago's Sears Tower and bombing FBI offices in Miami and elsewhere.