In Champion v. State, 87 Nev. 542, 490 P.2d 1056 (1971), the State conceded that a proper cautionary instruction concerning an addict-informer's testimony was central to the case. Champion, 87 Nev. at 544, 490 P.2d at 1057. The finding was based on the State's admissions that the utilized addict-informer was "about as unreliable an addict-informer as you can have," and that the addict-informer's unreliability was commonly known. Id. In Champion, the State further conceded that, aside from the addict-informer's testimony, there was "nothing to show that the drugs were turned over to the addict-informer and received from the defendant." Id. at 543-44, 490 P.2d at 1056.