Looking at the list of the shooter's victims here, I notice a couple of interesting things. They've probably been noticed by the cops already, but anyway:
- except for the 13-year-old boy, no male under 39 was shot. In other words, no males between 14 and 38 have been shot.
- 4 out of 6 shown male victims were wearing beards of some kind (at least in the photos provided, whether they were clean-shaven or not at the time I don't know)
- the last seven victims have alternated between black and white.

Many (but not all) hunters given a chance would like to shoot a "prize buck," the largest, most fit male of the herd. This shooter appears to target mainly older men and women. To be very crass about it, in the shooter's mind could he be "culling the herd?" Or, could he identify with 14 to 38 year old males? Or, could they just not be on his radar screen?

Also, the interactive timeline linked on the right side of this page is informative.

Here are the times between shots:
3 and 4: 31 minutes
4 and 5: 25 minutes
5 and 6: 81 minutes

Shots 5 and 6 are separated by just 5 miles, and took place on what looks to be the same street. So, what was the shooter doing in the time span of almost an hour and a half? Was he just driving around, and it took longer to find a victim than in the other cases? Did he drive south and check out the area around where shooting 7 occurred? Was he driving by the previous shooting locations to see what the cops were doing?

Or, did he stop somewhere and perhaps listen to a police scanner or a news radio station? Are there parks on or near Connecticut Ave? Or, perhaps a McDonalds or some other restaurant, or a gas station? Or, assuming that he has some kind of job, did he pick up or deliver something as part of that job?