Since Westerfield is in jail and has been since February, one can assume that if this was occurring on one of his computers, it had to be someone in San Diego law enforcement, not Westerfield. Which brings to mind the porn surfing on February 4th--it could not have been DW; Neal said it was not him. If we are to believe Neal, as Nasty Grace and others insist we must, then that leaves...
(drum roll please)
THE SAN DIEGO POLICE!
...or maybe it was Neal, and maybe Neal perjured himself on the stand.