Appellant appeals his conviction of one count of possession of a controlled substance — cocaine, codified at D.C.Codе § 33-541(d) (Supp.1984), on the grounds that (1) the trial court erred in permitting a police expert witness to testify concerning the significance of various chemicals аnd paraphernalia found during the search of appellant’s bedroom; (2) the expert’s testimony regarding a usable amount of cocaine was not credible and therefore there was insufficient evidence to support his conviction; and (3) references to the weapons seized from the sаme places as the drugs were prejudicial and should have been excluded. We affirm.
I.
On February 20, 1982, at approximately 1:00 p.m., two detectives of the Mеtropolitan Police Department executed a search warrant at 3406 Twenty-third Street, Southeast. The officers discovered appellant аnd a friend in an upstairs bedroom. During a search of the bedroom, the officers discovered a packet of white powder and a shotgun under the bed. They also discovered several packages of white powder elsewhere in the room, and in a hole in the floor of the bedroom closet, a brown bottle containing a white powder, a revolver, measuring spoons, and several one dollar bills covered with a white residue. Chemical analysis revealed that the powder found under the bed contained eleven percent cocaine; the other powders seized contained substances that were either not controlled substances or only trace quantities of controlled substances. Appellant was charged with possession оf the cocaine retrieved from under the bed.
At trial, the detectives testified about all the items seized during the search. A chemist testified to the quantity and contents of each of the powders. 1 Detective Johnny St. Valentine Brown qualified as an expert on the use and sale of cocaine, and testified that approximately 200 milligrams of a substance, eleven percent of which was cocaine, was a usable amount of the drug. On cross-examination he testified that 201 milligrams of a powder containing cocaine is a usable amount “regardless” of the proportions “because the total mass is utilized.” He further explained that “[the *1232 powder] would be a usable amount in the sense that no one utilize[s] or administer[s] pure cocaine. It is always diluted with cutting reagents.” Detective Brown testified, without objection, to the use of the various substances seized from the bedroom as “cutting reagents” to dilute cocaine and heroin. He also identified some of the packages of white powder seized from the bedroom as the type of packaging frequently used to distributе cocaine and heroin.
II.
Appellant challenges Detective Brown’s testimony about the use of the various substances found in the house as “cutting reagents.” This was not “other crimes” evidence since possession of these substances is legal. Nevertheless, appellant contends that the testimony was unduly prejudicial because it tended to suggest he was engaged in the sale and distribution of drugs when he was charged only with possession. The government contends that the evidence was probative of appellant’s knowledge of the existence of the drugs under the bed because the other substances and packages were found in the open in various parts of the room.
Whether evidence should be excluded as more prejudicial than probativе is a decision committed to the sound discretion of the trial court.
See Willcher v. United States,
(1) the subjeсt matter ‘must be so distinctively related to some science, profession, business or occupation as to be beyond the ken of the average layman [emphasis added]’; (2) ‘the witness must have sufficient skill, knowledge, or experience in that field or calling as to make it appear that his opinion or inference will probably aid the trier in his search for truth [emphasis added]’; (3) expert testimony is inadmissiblе if the state of the pertinent art or scientific knowledge does not permit a reasonable opinion to be asserted even by an expert.’
Dyas v. United States,
Since there was no objection to this evidence — either as a threshold matter (more prejudicial than probative) or as an evidentiary matter (a question of the method of proof) — the trial court did not have an opportunity to state its reasons on the record, and appellant must demonstrate “plain error.”
Watts v. United States,
Appellant also contends that Detective Brown’s testimony concerning whether the сocaine was a “usable amount” was inherently incredible and therefore appellant’s conviction cannot
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stand. The government must prove that the cocaine was more than a mere trace and that it was a usable amount.
Edelin v. United States,
Finally, appellant contends that the testimony сoncerning the weapons discovered during the search was unfairly prejudicial. However, this evidence was admissible to explain the circumstancеs surrounding the search and the arrest.
See Toliver v. United States,
Accordingly, the judgment below is
Affirmed.
Notes
. The package from under the bed contained 201 milligrams of powder, 22 milligrams of which were cocaine and the rest was tetracaine. The othеr packages contained manitol, quinine hydrachloride, dextrose, tetracaine, anositol and quinine. Some of the other packages contained “traces” of heroin, cocaine, quinine and tetracaine.
