In the course of reporting Wednesday on the allegations of test tampering in the D.C. schools, I discovered a study commissioned by the school system that they apparently have never released. It may be unrelated to the greater issue of whether educators changed wrong answers to right ones to make their schools look good, but I thought I ought to report it even though it did not fit in my piece about Adell Cothorne.

D.C. schools spokeswoman Melissa Salmanowitz said D.C. leaders asked Caveon Test Security to interview educators at certain schools in 2011 about testing procedures on the DC-CAS annual test in 2010. Caveon had done an investigation of 2009 testing, some of which the school system revealed. But this 2010 testing study appears to have remained hidden and, according to Salmanowitz, will remain that way.

She told me about the study because she is trying to discredit Cothorne’s account, a version of events Cothorne has told PBS, a federal court and me. Cothorne has said that she found signs of test tampering at the Noyes Educational Campus when she was principal there from 2010 to 2011. Cothorne does not appear to remember a visit by Caveon to Noyes that Salmanowitz said took place on March 17, 2011, when she was asked about test security in 2010.

Salmanowitz said most of the questions to Cothorne from Caveon got “not applicable” answers because Cothorne was still working in Montgomery County when the D.C. tests were given in April 2010. But she did answer this question: “Can you think of anything that would improve the testing process, test integrity or test security?” She said no.

I haven’t reached Cothorne to get her view on this yet, but she had spoken to Caveon investigators the previous fall about 2009 testing at Noyes, and she told them that didn’t know anything. She couldn’t critique testing procedures she had not seen.

But I also know that at that point she was careful not to raise a ruckus about the test tampering she had seen in November 2010, since her efforts to report it had produced a campaign of threats and harassment against her she felt was orchestrated by the former principal at Noyes. She was thinking at that point she wanted to get out of Noyes quietly for her peace of mind, if nothing else.

Those who think the D.C. inspector general didn’t need to talk to her because the U.S. Education Department inspector general did talk to her have not read the DC IG report. It says nothing about what she told the Ed Department IG — which is not part of the D.C. government — because she spoke to the Ed Department long after she left the school. The DC IG was supposed to tell us what was going on at Noyes. It didn’t.

But we won’t see that Caveon report on 2010 testing. Salmanowitz said it won’t be released. She declined to say why.

This post has been updated.