          IN THE COURT OF CRIMINAL APPEALS OF TENNESSEE

                                 AT JACKSON             FILED
                          NOVEMBER 1997 SESSION        November 25, 1997

                                                       Cecil Crowson, Jr.
                                                        Appellate C ourt Clerk
STATE OF TENNESSEE,                  )
                                     )    NO. 02C01-9705-CC-00183
      Appellee,                      )
                                     )    HARDEMAN COUNTY
VS.                                  )
                                     )    HON. JON KERRY BLACKWOOD,
RANDY JOY,                           )    JUDGE
                                     )
      Appellant.                     )    (Delivery of Cocaine)



FOR THE APPELLANT:                        FOR THE APPELLEE:

JEANNIE KAESS (At Trial)                  JOHN KNOX WALKUP
Assistant District Public Defender        Attorney General and Reporter
P. O. Box 700
Somerville, TN 38068                      KENNETH W. RUCKER
                                          Assistant Attorney General
C. MICHAEL ROBBINS (On Appeal)            Cordell Hull Bldg., 2nd Floor
3074 East Street                          425 5th Avenue, North
Memphis, TN 38128                         Nashville, TN 37243-0493

                                          ELIZABETH T. RICE
                                          District Attorney General

                                          JERRY W. NORWOOD
                                          Assistant District Attorney General
                                          302 Market Street
                                          Somerville, TN 38068




OPINION FILED:



AFFIRMED



JOE G. RILEY,
JUDGE
                                   OPINION


       The defendant, Randy Joy, was convicted by a Hardeman County jury of

delivering cocaine over 0.5 grams, a Class B felony. Defendant was sentenced as

a Range I, Standard Offender, to a term of eleven (11) years in the Tennessee

Department of Correction and fined in the amount of $5,000. Defendant presents

the following issues for our review:

       (1)    whether a proper foundation was laid for the testimony
              of the drug analyst concerning the weight of the
              cocaine;

       (2)    whether the trial court should have admitted evidence
              relating to the informant’s girlfriend handling cocaine;
              and

       (3)    whether defendant’s prior drug conviction was properly
              admitted.

We affirm the judgment of the trial court.



                                       FACTS



       Although sufficiency of the evidence is not an issue in this appeal, a brief

recitation of the facts is appropriate. The local Drug Task Force employed a

confidential informant as a part of an undercover drug operation. The informant

arranged a narcotics transaction with the defendant. The narcotics agent gave the

informant $100 to be used in the purchase of cocaine and wired the informant.

       The confidential informant met the defendant at a prearranged location. The

defendant requested the money, and the confidential informant gave him $80.

Defendant departed in his vehicle and returned approximately fifteen minutes later.

Defendant then handed the confidential informant a plastic bag containing five (5)

rocks of crack cocaine. The narcotics agent followed the informant back to his

mobile home and obtained possession of the narcotics and the recorder.




                                         2
               TESTIMONY CONCERNING WEIGHT OF COCAINE



       The state presented evidence from a forensic scientist specializing in drug

identification. When the witness testified that “I weighed it . . . I determined that the

substance weighed .6 grams,” defense counsel objected. The basis of the objection

was a failure to lay a proper foundation regarding the accuracy of the measuring

instrument. The objection was overruled. Defense counsel did not cross-examine

the witness.

       Defense counsel has not cited nor have we discovered any case requiring

that a forensic scientist testify as to the calibration and accuracy of a weighing

instrument prior to being allowed to testify as to the weight of a particular substance.

Tenn. R. Evid. 705 provides that experts may express opinions and give reasons

without the prior disclosure of the underlying facts or data, unless required by the

court. The rule further provides that the expert may be required to disclose the

underlying facts or data upon cross-examination. Defense counsel chose not to

cross-examine the witness concerning the weighing instrument.

       Defendant primarily relies upon State v. Sensing, 843 S.W.2d 412 (Tenn.

1992), which established certain minimal requirements relating to the admissibility

of the results of a breath testing device. Sensing is distinguishable. Police officers

are not recognized as experts on blood alcohol concentration or the manner in

which certain instruments perform this measurement. The forensic scientist who

determined the weight of this controlled substance was recognized as an expert

witness.   As such, her testimony is controlled by the law relating to expert

witnesses. Certainly, defense counsel was free to cross-examine the witness

concerning the accuracy of the weighing instrument. However, we find no reason

to extend Sensing to forensic scientists who testify concerning the weight of a

particular substance.

       This issue is without merit.




                                           3
                            BIAS OF THE INFORMANT



       The defense called as a witness an officer who had worked with the

informant. The defense endeavored to introduce a videotape of a transaction in an

unrelated case. Defendant contends that the tape shows the informant’s girlfriend

handling cocaine during a transaction. Defense counsel contends this is relevant

to show the bias of the informant toward the state in order to prevent the

prosecution of his girlfriend for handling the cocaine. The trial court disallowed the

testimony.

       Certainly, evidence of bias of a witness is relevant and admissible. Tenn. R.

Evid. 616; State v. Williams, 929 S.W.2d 385, 389 (Tenn. Crim. App. 1996).

However, no party may examine a witness upon irrelevant matters. Tenn. R. Evid.

402. The propriety, scope, manner and control of the examination of witnesses is

a matter within the discretion of the trial court, subject to appellate review on an

abuse of discretion standard. State v. Caughron, 855 S.W.2d 526, 540 (Tenn.

1993), cert. denied 510 U.S. 979, 114 S.Ct. 475, 126 L.Ed. 2d 426 (1993).

       We find no abuse of discretion by the trial court in this instance. There was

no showing that the drugs allegedly handled by the girlfriend were not properly

handed over to authorities. Defendant simply contended she did not have the

authority to handle the drugs, and her handling of the drugs would be a criminal

offense. We fail to see how this testimony would have shown bias on the part of the

informant. At most, the failure to admit such evidence was harmless error. Tenn.

R. App. P. 36(b).

       This issue is without merit.



                              PRIOR CONVICTIONS



       Prior to defendant’s testimony, the trial court ruled that the defendant could

not be impeached by a prior conviction for the sale of cocaine. During defendant’s

direct examination, he was asked whether he delivered the cocaine to the informant.


                                          4
He remarked, “I don’t do drugs; I don’t sell drugs.” Defendant further stated on

three other occasions that he did not sell drugs. The prosecuting attorney secured

permission of the trial court at a bench conference to ask about the prior conviction

in light of this testimony. The trial court found that the defendant “made a blanket

statement that he doesn’t sell drugs” and opened the door for admission of the prior

drug conviction. Upon cross-examination, the prosecuting attorney asked the

defendant about the prior drug conviction.

       We conclude that the defendant’s testimony opened the door to the state’s

cross-examination about the previous drug conviction. See State v. Bray, 669

S.W.2d 684, 687 (Tenn. Crim. App. 1983). In fact, the defendant stated on four

separate occasions that he did not sell drugs. This clearly left the implication that

he had never been involved in the sale of drugs. The state had a right to challenge

the implication left with the jury. The trial court did not abuse its discretion in

allowing the introduction of this evidence.

       This issue is without merit.



                                  CONCLUSION



       The judgment of the trial court is affirmed.




                                                 JOE G. RILEY, JUDGE




                                         5
CONCUR:




GARY R. WADE, JUDGE




DAVID G. HAYES, JUDGE




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