This article documents the decline and stabilization of the number of adjudicated due process hearings between 2006 and 2012 across the country.
Zirkel notes that while innovations such as resolution meetings, mediations, and facilitated IEP meetings are possible contributors, other factors--such as local changes in trends and services in the District of Columbia (which accounted for 71% of the decrease of the overall reduction nationally)--may be more explanatory.
Further analysis focuses on the wide variation across jurisdictions of the filings-to-adjudications ratios. "[A]mong the eleven leading jurisdictions, the ratios varied from Puerto Rico (1.84) and District of Columbia (2.46) to Massachusetts (28.52) and California (28.92)" (p.10).