The jury convened about 9:15 a.m., before Cousineau returned to the stand.
Cousineau served a dual role as both Madigan's issues director and political director of the Democratic Party of Illinois.
In exchange for his testimony, the government served Cousineau with a letter of immunity, which essentially says he cannot be charged if he testifies truthfully.
During his testimony, Cousineau has given an inside look into how the speaker's office operated under Madigan, and the people who were part of his inner circle, including himself, Chief of Staff Tim Mapes, Heather Weir Vaught, Craig Willert and Mike McClain, among others. Of those, only McClain was not directly employed as part of the speaker's staff.
""The speaker would be the ultimate decision-maker," Cousineau said.
Testimony centered on Cousineau's role in the efforts to get two big pieces of legislation passed: EIMA in 2011 and FEJA in 2016. The two bills are at the heart of the government's corruption case against Madigan and McClain, as it relates to the ComEd portion of the indictment, specifically.
While Cousineau was not directly involved in the 2011 passage of EIMA or Smart Grid, Cousineau testified to how the speaker would often substitute members out of committees when they needed to get specific bills voted out onto the floor, and they knew the regular members would vote against the bill.
By November of 2016, Cousineau was part of several working group meetings regarding ComEd's second big legislative push, FEJA.
Mike Madigan trial LIVE updates: Former aide testifies in ex-Illinois speaker's trial
McClain, who was during the entire time a contract lobbyist for ComEd, was also a part of the working groups. Cousineau said he served a dual role.
"Mr. McClain certainly explained or talked about what the company was looking for. But he was also there as strategic advisor to the speaker," Cousineau said.
During the days leading up to the Dec. 1, 2016 vote, which ultimately saw FEJA become law, it became apparent that there weren't enough Democratic votes to pass the legislation. Cousineau and his staff, along with the Sierra Club, set out to convince members to sway their votes.
"I just talked to them about the bill, why they should support the bill," Cousineau said. "We wanted to get the bill passed out of the House of Representatives."
Through emails, phone calls and text messages shown to the jury Wednesday, the government painted a picture in which Madigan's close friend and co-defendant McClain was always in the background, even while not directly employed by the speaker. A contracted lobbyist with ComEd, McClain appeared to always be in the room during important negotiations.
Often during his testimony, Cousineau has seemed reluctant to answer or does so in a low voice.
This is the third time Cousineau has been called to testify in a federal case related to Madigan. He was previously called both during the ComEd Four Trial and during the perjury trial of Tim Mapes, Madigan's former chief of staff.
But, the most critical part of Wednesday's court proceedings may have taken place without either Cousineau or the jury in the room, following a line of questioning that related to Cousineau's secondary role as political director of the Illinois Democratic Party.
For nearly an hour, defense attorneys argued that the jury was being unfairly tainted, as the government tried to paint a picture of an all-powerful speaker, who could withhold campaign contributions to specific House members if they did not vote a certain way.
This came as prosecutors tried to convince jurors that Madigan, through McClain, solicited bribes, along with no-work jobs and contracts from ComEd and others in exchange for favorable legislation.
The issue for now remains unresolved, but is expected to be taken up again Thursday before the jury is convened. Will Cousineau will also return to the stand.
Court wrapped up about 2:30 p.m., with Wednesdays being designated as early days for the duration of the trial.
Ex-ComEd attorney Tom O'Neill testified for much of the day Tuesday in Madigan's trial.
He spoke of former Illinois House Speaker Mike Madigan's influence in the naming of Juan Ochoa to the ComEd Board.
The former Illinois House speaker is accused of a sophisticated bribery and racketeering scheme.
The trial could last three months.
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