Nearly a year after the reforms were adopted, heres a look at the four changes that have caused the most rancor and are expected to have the greatest impact in stabilizing matters.

The Labor secretary says Gov. Jerry Brown's reform plan diminishes both the substantive rights of transit employees under current collective bargaining agreements and narrows the future scope of collective bargaining over pensions.

Banks, bond insurers, employee pension systems and others standing to lose big if a federal judge declares Detroit insolvent are expected to legally file their objections to the largest municipal bankruptcy in U.S. history.

Assets in these retirement plans totaled $750 billion in 2010 and, if projections hold true, could hit $1 trillion by 2016.