Read enough search warrant applications, and "CI" (confidential informant) will rear its head again and again.

Praised be Virginia’s Court of Appeals (albeit by only 2-1) for reversing a conviction that resulted from a so-called reliable confidential informant’s tip that the defendant was about to arrive armed at the Harris Teeter for a drug deal, but where insufficient grounds were stated for such a belief:

"Under the totality of the circumstances, we hold that the CI’s tip in this case did not provide the officers with probable cause. The CI did not provide his basis of knowledge, nor did he provide such detailed information that it could be inferred he had personal knowledge of the criminal activity. Finally, his history of reliability was not so unusual on its own to support a finding of probable cause. For these reasons, we hold that under the totality of the circumstances, the police officers lacked probable cause for the warrantless search of the vehicle and appellant." Byrd v. Virginia, ___ Va. App. ___ (March 9, 2010). Jon Katz