Opinion
Buford Houston Robertson, Jr. appeals his convictions of four counts of distribution of cocaine. He challenges: (1) the testimony of the Commonwealth’s expert witness regarding the definition of a Schedule II drug; (2) the chain of custody; and (3) the sufficiency of the evidence.
On appeal, we view the evidence in the light most favorable to the Commonwealth.
Higginbotham v. Commonwealth,
Floyd J. James, a convicted felon and former drug user, worked as an “undercover agent” for the Danville Police Department. James had known the defendant for about thirteen years. On four *856 occasions, James purchased varying amounts of cocaine from the defendant. Before each sale, James met with police officers who searched him, fitted him for a hidden voice transmitter, provided him with cash, and sent him out looking for Robertson to purchase cocaine. On three separate occasions, James paid Robertson cash and received cocaine directly from him. Audio tapes were made on each of these occasions, which were introduced at trial.
Robertson asserts the trial court erred by allowing the Commonwealth’s expert witness to classify cocaine as a Schedule II substance, and to testify further as to the definition of a Schedule II substance. We agree with Robertson’s argument that “the testimony was irrelevant to the issue.” The Commonwealth’s expert defined a Schedule II substance as “any substance that has a high potential for abuse and has limited medical use,” which is simply the statutory definition. Testimony designed to establish matters of law “has no probative value” and should not be allowed.
State Farm Mut. Auto. Ins. Co.
v.
Smith,
Robertson next alleges that the Commonwealth failed to establish a continuous chain of custody of the cocaine seized from his home. The evidence reveals that the police mailed the cocaine to the laboratory in sealed packages, with identifying markings. The Commonwealth’s expert witnesses testified that the packages were received by an authorized agent at the laboratory, and when received each package was still sealed with police evidence tape. Therefore, the only possible break in the chain of custody was the period of time when the cocaine was in the hands of the Postal Service.
In the absence of clear evidence to the contrary, courts may presume that public officers have properly discharged their official
*857
duties.
Smith
v.
Commonwealth,
The purpose of the chain of custody rule is to establish that the evidence obtained by the police was the same evidence tested. “[Wjhere the substance analyzed has passed through several hands the evidence must not leave it to conjecture as to who had it and what was done with it between the taking and the analysis.”
Horsley
v.
Commonwealth, 2
Va. App. 335, 338,
(5) Finally, Robertson challenges the sufficiency of the evidence to support his convictions. His argument focuses on the testimony of the Commonwealth’s key witness, Floyd James. The credibility of all witnesses and the weight accorded their testimony are matters solely for the fact finder, who has the opportunity of seeing and hearing the witnesses.
Schneider
v.
Commonwealth,
230 Va.
*858
379, 382,
Accordingly, the convictions appealed from are
Affirmed.
Koontz, C.J., and Benton, J., concurred.
