They say having law enforcement expert Gregory Lee present is essential to the trial because he might be able to find problems with the role of the government's informants.
But last week, Kugler said he was not sure how much Lee would add to the defense.
On Tuesday, the judge plans to hold a hearing in which Lee will be present and decide whether the trial should start on Sept. 27.
The defendants could face life in prison if they are convicted.
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