He goes from Goldman Sachs to Treasury Secretary, where he blows up regulation of Wall Street, then on to Citibank where he gets a $20 million per year position with no management responsibility or accountability. That was a condition of him taking the job at Citi. He basically used his political connections for Citi's benefit and advised management at Citi to ramp up risk.
And even after Citi and Wall Street blew up, Rubin's inner circle still dominates the Treasury Department under Obama and no doubt would in a Hillary Clinton administration.
http://www.americanbanker.com/news/law-regulation/the-long-shadow-of-robert-rubin-1071601-1.html
Clinton administration officials, for example, pushed for the passage of the Gramm-Leach-Blilely Act, which repealed a Depression-era provision separating commercial banking from more risky activities and codified the merger that led to megabank Citigroup.
"Bob Rubin and his administration blessed the universal banking model and embraced it and said, make that happen,'" said Wilmarth.
Critics, including Warren, see this as a crucial moment, one that allowed the biggest institutions to become even larger and more complex, eventually forcing the government to bail them out. (Warren has co-authored a bill to undo Gramm-Leach-Bliley and bring back the old Glass-Steagall Act restrictions.)
Adding fuel to the fire, Rubin decamped from Treasury in 1999, shortly after the passage of Gramm-Leach-Bliley, to join Citigroup, which at the time was the principal benefactor from the law. He has become Exhibit A when progressives talk about the "revolving door" between banks and Washington.
In a speech on Tuesday to advocacy groups, Warren cited Rubin by name, noting that three of the last four Treasury secretaries under Democratic presidents, "starting with Robert Rubin," have been affiliated with Citigroup either before or after their service.