Historical clue formulations

• Corruption — 2020-06-12
• Bribery and such — 2015-12-08
• Tammany Hall problem — 2013-06-16
• Surgeon's procedure — 2010-10-03
• Transplant, of a sort — 2004-10-12
• Payola — 2004-04-23
• Add on, as to a plant — 2003-12-01
• Firmly add on — 2003-11-29
• Some corruption — 2003-03-18
• Payola — 2001-02-18
• White collar crime — 1997-11-13
• Payola, e.g. — 1996-02-13