On one occasion alone, investigators confiscated 44 pounds of cocaine in a huge safe, machine guns, thousands of rounds of ammunition, ballistic vests, drivers' licenses, business cards, an aircraft registration, an automobile registration, coded customer lists, and more financial records.
Informants have helped identify various theft and narcotics rings, vice operations, gang affiliates, and sex offenders. And the beautiful thing is that once successfully tested, their information is often court viable, even if they don't enjoy a particularly high batting average in payoffs. You don't have to continually re-establish your informant's credibility once he or she has passed judicial muster.
But the same traits that render them vulnerable and willing to perform as informants can make them liabilities, too. With moral barometers as suspect as their loyalties, they are apt to sell you out as readily as anyone else. Never put yourself in a position where your informant finds he has one more "get out of jail" chip to play: you.
While "stop the snitching" campaigns have taken their toll on the informant pool, there will always be those who will work for us given sufficient provocation.