In People v. Woods, 214 Ill. 2d 455, 467, 828 N.E.2d 247, 293 Ill. Dec. 277 (2005), the defendant tried to avoid his forfeiture of a chain-of-custody objection by framing his argument on appeal as a challenge to the sufficiency of the evidence. (The problem was one of how broadly a court should read a stipulation regarding the testimony of a forensic chemist.) The Woods court stated: "We reject the notion that a challenge to the State's chain of custody is a question of the sufficiency of the evidence. A chain of custody is used to lay a proper foundation for the admission of evidence. Accordingly, a defendant's assertion that the State has presented a deficient chain of custody for evidence is a claim that the State has failed to lay an adequate foundation for that evidence. Thus, a challenge to the chain of custody is an evidentiary issue." Woods, 214 Ill. 2d at 471. "When there is a complete failure of proof, there is no link between the substance tested by the chemist and the substance recovered at the time of the defendant's arrest," and the State's failure to present a sufficient chain of custody would lead to the conclusion that the State could not prove an element of the offense: the element of possession. Woods, 214 Ill. 2d at 472.