Thanks for sharing this, and I look forward to seing the finished product of your research.

I think the raid you mentioned is the same raid mentioned by Bingham in his explanation/defense of his Order No. 11 painting:

"It has been asserted, in a respectable quarter, that this unprecedented measure (Order No. 11) was warranted by a military necessity as the only means of ridding the district of the banditti by which it was infested. But much the largest portion of this banditti were in daily and fraternal association with the Federal troops, and perpetrated their robberies and murders under their patronage and protection. The others. professing to act under Confederate authority, were too insignificant in numbers to have maintained themselves in the district against any serious effort on the part of the military to expel them. The frequent raids of the latter, pretendedly for this purpose, were really directed against the unarmed inhabitants, more than thirty of whom, in one raid, were murdered in cold blood."