Sharpe's BMI was well established when Charlie Wright, a young black man, arrived at Union lines from Culpeper, Virginia, in June 1863. While being debriefed, his extensive knowledge of units in Lee's army became apparent. He had an excellent memory for details. On 12 June, Capt. John McEntee, an officer from the BMI who had deployed with Union cavalry forces just after the battle of Brandy Station, telegraphed Sharpe the following: "A contraband captured last Tuesday states that he had been living at Culpeper C. H. for some time past. Saw Ewells Corps passing through that place destined for the Valley and Maryland. That Ewells Corps has passed the day previous to the fight and that Longstreet was them coming up." Shortly thereafter, McEntee also reported that Wright was well acquainted with these two corps and that he believed Wright's information was reliable. Wright identified more than a dozen separate Confederate regiments from both Ewell's Corps and Longstreet's Corps. The key intelligence Wright provided was that these troops had passed through Culpeper bound for Maryland.