District Councilman David Catania has publicly criticized DC Public Schools officials for their lack of progress in raising test scores, curbing truancy and improving the District’s dismal high school graduation rate. But there’s one dark corner where even the outspoken Education Committee chairman refuses to go.

A just-released 2009 internal memo to former Chancellor Michelle Rhee from her own outside data analyst, Fay “Sandy” Sanford, warned that the statistically improbable level of wrong-to-right erasures on the District’s standardized tests implicated 191 DCPS teachers in 70 schools with “possible testing infractions.”