Former Gov. Jim Edgar’s pension compromise with House Speaker Mike Madigan in the 1990s set the state’s pension funds down an unsustainable road.

Under former Gov. Jim Edgar’s pension ramp, unfunded pension liabilities have increased nearly $100 billion despite taxpayers contributing $16.4 billion more to the five state-run pension systems than required under the Edgar plan.

There’s immense pressure on Illinois legislators to pass a pension bill. With the state pension system nearing insolvency and credit agencies warning of further downgrades, the perceived wisdom is that any pension fix, no matter how small, is a “step forward” that must be passed. But when it comes to pension reform in Illinois, that...