That count claims Madigan used his influence to get AT&T to pay former state Rep. Eddie Acevedo more than $20,000 for a no-work consulting contract.
Prosecutors want to call Acevedo to the stand Wednesday.
His attorney said Acevedo has been diagnosed with dementia, and is not competent to testify.
The attorney did not provide medical records.
Acevedo was in court Tuesday, and interviewed by the judge to determine whether he is competent to take the stand as a government witness.
The judge's decision regarding Acevedo's testimony could determine whether the government is able to wrap up its case against Madigan this week or next at the Dirksen Federal Building.
Monday was an unusually short day in the corruption trial of Michael Madigan.
Madigan and co-defendant Mike McClain face bribery and racketeering charges.
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