The Colorado Supreme Court has issued an opinion in Aloi v. Union Pacific R.R.
This is the opening paragraph of the opinion: "Petitioner Frank Aloi brought a personal injury action against Union Pacific Railroad (UP). Prior to trial, UP destroyed documents relevant to the litigation. As a sanction for spoliation of evidence, the trial court instructed the jury it could draw an inference that the evidence contained in the destroyed documents would have been unfavorable to UP. The trial court gave the adverse inference instruction three times, one time interrupting a crossexamination to provide the instruction. The jury returned a verdict for Aloi, and UP appealed. The court of appeals reversed the trial court's judgment. The Supreme Court granted certiorari."
The holding? "We hold that the trial court did not abuse its discretion by providing the jury with an adverse inference instruction as a sanction for the spoliation of evidence where it found that UP willfully destroyed relevant evidence, which otherwise naturally would have been introduced at trial. Second, we hold that the trial court did not abuse its discretion by repeating the adverse inference instruction because the trial court addressed appropriate objections and articulated the reasoning for its decision; nor did the trial court abuse its discretion by interrupting the crossexamination because it acted to remedy prejudice and as a result did not depart from the required impartiality so as to deny the defendant a fair trial."
The law in Tennessee on this issue is scarce; this opinion is a good place to start to convince a trial judge that an adverse inference instruction is warranted.