The backlog of clemency decisions was created under former Governor Rod Blagojevich. During his six years in office, he only decided on around 1,000 petitions. The rest were simply ignored and allowed to pile up. When Blagojevich was removed from office, roughly 3,000 sat pending for incoming Governor Pat Quinn.
Former Governor Quinn acted on 4,928 petitions during his six years in office, granting 1,795 of them. Quinn's batches of clemency decisions typically mixed newer petitions in with older ones. So while Quinn decided on more petitions than the backlog he inherited, some petitions filed under Blagojevich remained when Quinn left office.
Gov. Rauner, by contrast, has mostly decided on petitions by order of filing. In his two years as governor, Rauner has acted on 2,333 clemency petition, granted 80 pardons and three commutations. With yesterday's release, Rauner has completely worked through the remaining petitions filed before he took office.
In the AP article, Rauner acknowledged that he is not as good as Quinn was when it comes to granting petitions, but defended himself by pointing at governors in some other states who are even less merciful.