Yes, it was the shooting of Pascal Charlot, the Haitian man, at the corner of Georgia Ave. and Kalmia Rd., NW D.C. at 9:20 PM the evening of Thursday Oct. 3rd. According to a Washington Post article, a police dog alerted to the presence of gunpowder at a Presbyterian church at that corner. I believe I have read Charlot was waiting at the corner to cross the street.
This is the site I took a look at Saturday afternoon, and to which I observed you would have a clear line of sight to shoot from on the roof and upper stories of the Ramada Inn three or four blocks north of the site. The fact that a police dog alerted for gunpowder at that church wall need not mean that the shot that killed Charlot came from there.
The police have not been releasing info about the trajectory of the snipers' shots. They may be able to tell from what height the shots came. Charlot was shot in the neck. I think it would be easier to hit him there if you were shooting from above.
The second to the last sniper shooting (at the gas station in Manassas) I saw an officer holding up a piece of wood about 20-24 inches long...it was tilted back end up towards the pump at about an 10 degree angle...I was interested in that piece of footage because I believe he was trying to gauge the angle of the shot...and I do believe that the shots are being fired from the proverbial "grassy knoll" types of areas and NOT from a vehicle.