Appellant was convicted of aiding and abetting in the delivery of methamphetamine in violation of §§ 6-l-201(a), W.S. 1977, 35-7-1031(a)(ii), W.S.1977, Cum.Supp.1985, and 35-7-1016(d)(ii), W.S.1977, Cum.Supp.1985, and delivery of methamphetamine in violation of § 35-7-1031(a)(ii), W.S.1977, Cum.Supp.1985. She raises the following issues on appeal:
“I. Whether the Defendants have been denied due process and equal protection of the law by the actions of the prosecution in deliberately avoiding the preliminary hearing and obtaining indictments without observing minimal standards of fundamental fairness.
“II. Whether the current grand jury was improperly impaneled under Section 7-5-102 in that there was no necessity for said body, requiring the dissolution of the panel and the dismissal of the indictments.
“III. Whether the indictments in these cases are fatally defective for failure to conform to the statutory requirement that the foreman endorse the words ‘A True Bill’ upon each indictment.
“IV. Whether the indictments should be dismissed because the conduct of the grand jury lacks any indicia of reliability in the assessment of probable cause.
*854“V. Whether the two tape recordings were erroneously admitted under the co-conspirator exception to the hearsay rule.
“VI. Whether the prosecutor’s question and gesture directed at Appellant’s boyfriend resulted in Appellant being denied a fair trial.
“VII. Whether the Court can require a Defendant to pay for costs of prosecution as a part of her sentence.”
The first four issues concerning the grand jury are the same issues presented to this court in Hennigan v. State, Wyo., 746 P.2d 360 (1987). We determined that there was no error with respect to those issues in Hennigan; and, for the reasons stated, we hold there was no error here with respect to issues I-IV. Upon the balance of the issues presented in this case, we affirm but modify the sentence to delete the conditions of probation requiring payment of costs of prosecution and reimbursement of attorney fees.
FACTS
On January 17,1985, appellant’s husband Mike Burke, Gus Skurdal, and David Lauck met at Decker’s East grocery store on Highway 59 in Campbell County. At that meeting Mr. Lauck, an undercover narcotics agent for the Campbell County Sheriff’s Office, arranged to buy a half ounce of methamphetamine from Burke. Lauck “fronted” $1,100 to Burke and agreed to pick up the methamphetamine at Burke’s residence the next day. When Lauck arrived at the Burke residence (a “trailer house” shared by appellant, Burke, and Skurdal), appellant was home, but Burke was not. Appellant suggested to Lauck that they search downtown for Burke. Lauck agreed and then drove appellant to several bars and a haircutting establishment in the downtown area. At each stop Lauck waited in the car while appellant went inside each establishment to search for her husband. She did not find him. Lauck drove her home, and she told Lauck that her husband would call him later, once he came home. Mike Burke called Lauck that evening from the trailer house and told him that he could come over and pick up the methamphetamine. Lauck drove to the Burke residence where Mike Burke gave him the methamphetamine. Appellant and Gus Skurdal were present when the transaction occurred.
On May 22, 1985, Gus Skurdal called Agent Lauck to set up another methamphetamine transaction. Lauck testified that he went to the Burke residence later that day and gave appellant $200 in exchange for two and one-half grams of methamphetamine. Appellant testified that she had no recollection of this transaction because on the day in question she was under the influence of medication prescribed by her dentist.
THE CO-CONSPIRATORS’ STATEMENTS
During direct examination of Officer Lauck, the prosecutor offered into evidence two audio tapes and requested that they be played for the jury. The first tape, offered in support of Count I, contained a January 17, 1985 telephone conversation between Agent Lauck and Mike Burke in which the two men set up the meeting at Decker’s. The second tape, offered in support of Count II, contained a May 22, 1985 conversation between Lauck and Gus Skurdal in which Skurdal told Lauck that he could come to the Burke residence to pick up two and one-half grams of methamphetamine from appellant. The defense objected to the admission of both tapes on the grounds of hearsay and confrontation. The trial court overruled the objections, concluding that the statements were admissible under Rule 801(d)(2)(E), W.R.E., as statements of a co-conspirator during the course of and in furtherance of a conspiracy. Appellant now argues that the trial court erred in admitting the two tapes because the State did not produce sufficient evidence of a conspiracy on either count.
Under the Wyoming Rules of Evidence a statement is not hearsay if
“[t]he statement is offered against the party and is * * * (E) a statement by a co-conspirator of a party during the course and in furtherance of the conspiracy.” Rule 801(d)(2)(E), W.R.E.
*855We have held that statements may be admitted into evidence under Rule 801(d)(2)(E) even if a conspiracy is not charged. Jasch v. State, Wyo., 563 P.2d 1327, 1333 (1977). In order for statements of a co-conspirator to be admitted under the rule, there must be prima facie evidence of a conspiracy independent of the co-conspirators’ statements. Dorador v. State, Wyo., 711 P.2d 417, 418 (1985). This burden is met if there is sufficient evidence to permit the trial court to reasonably infer that a conspiracy existed. Id. at 418-419.
Our general conspiracy statute defines the elements of conspiracy as: (1) an agreement between one or more persons to commit a crime, and (2) an overt act to effect the objective of the agreement. Section 6-1-303, W.S.1977.1 The existence of an agreement may be established through circumstantial evidence:
“One might suppose that the agreement necessary for conspiracy is essentially like the agreement or ‘meeting of the minds’ which is critical to a contract, but this is not the case. Although there continues to exist some uncertainty as to the precise meaning of the word in the context of conspiracy, it is clear that the definition in this setting is somewhat more lax than elsewhere. A mere tacit understanding will suffice, and there need not be any written statement or even a speaking of words which expressly communicates agreement. * * *
“Because most conspiracies are clandestine in nature, the prosecution is seldom able to present direct evidence of the agreement. Courts have been sympathetic to this problem, and it is thus well established that the prosecution may ‘rely on inferences drawn from the course of conduct of the alleged conspirators.’ ” (Footnotes omitted.) W. LaFave and A. Scott, Criminal Law (1972) at pp. 460-461.
With respect to Count I, the State introduced the following evidence through the testimony of Agent Lauck: Lauck met with Mike Burke and Gus Skurdal and “fronted” the money for the drug purchase. He went to appellant’s home to pick up the methamphetamine, and only appellant was there. Appellant told Lauck that her husband had acquired the methamphetamine and that it was of good quality. Appellant seemed afraid that Officer Lauck would be upset because the methamphetamine was not at the house at that time. At her own suggestion, she accompanied Lauck on a search for her husband; and, while on that search, she actively tried to find him. She continually reassured Lauck that the methamphetamine had been obtained and that he could get it from Mike Burke as soon as they found him. At this point in Lauck’s testimony the trial court correctly admitted the first tape. The testimony supported an inference that an understanding existed between appellant and her husband, the understanding being that appellant would assist in delivering the methamphetamine. Her active assistance satisfied the overt-act requirement.
With respect to Count II, Lauck testified that on May 22, after agreeing to purchase two and one-half grams of methamphetamine from Gus Skurdal for $200, Lauck went to appellant’s residence where he and appellant consummated the transaction on the same terms he had discussed with Skurdal. At this point the trial court admitted the second tape. This ruling was also correct, as the evidence supported an inference that appellant and Gus Skurdal agreed or understood that appellant would deliver the methamphetamine to Lauck. The delivery satisfied the overt-act requirement. The tapes were properly admitted.
PROSECUTORIAL MISCONDUCT
In his cross-examination of appellant, the prosecutor sought to establish that appel*856lant was a drug user and that drugs were often present in her home. At one point during his questioning of appellant, the following exchange occurred:
“Q. Okay. From June 6th to June 26th, you had friends over and you used drugs inside that trailer?
“A. No, I did not.
“Q. Well, weren’t you in bed with that man right back there when you were arrested and he had drugs?”
Defense counsel immediately objected, approached the bench, and asked for a mistrial:
“MR. WEERTS: I’d ask for a mistrial now. I think bringing up what Mr. Murray just did has totally ruined this case. She cannot get a fair trial, and I think that we must have a mistrial at this point. Bringing up the fact that she was arrested in bed with that man has nothing to do with the case.
“MR. MURRAY: There were drugs.
“THE COURT: It doesn’t have anything to do with the case. The fact that she might have been doing drugs, might have had drugs might have something to do with it, but the fact that she might have been in bed with someone has absolutely nothing to do with the case at all.
“And I’m going to admonish the jury that they will not, they will disregard that question and any possible answers, and I’ll warn you not to bring up those kinds of things again.
“I also want to tell you that it’s the rule in this courtroom that you conduct your examination from behind the podium.”
The court took the defendant’s motion under advisement, then instructed the jury as follows:
“Ladies and Gentlemen, I want to tell you that you are to disregard that last question asked by Mr. Murray. The question is of no significance to this case and has absolutely nothing to do with the guilt or innocence of the defendant, and you are to disregard it totally and any answer that might have been given to that.
“You are not to consider it when you deliberate this case.”
After the close of the evidence, defense counsel renewed his motion for a mistrial.2 The court denied the motion, explaining:
“Though I don’t think it’s improper to ask her about the drugs, I think the manner in which you asked it, Mr. Murray, when you asked, and I think Mr. Weerts is right — in very graphic detail— about whether she was in bed with this fellow was I think putting it very nicely — that you pointed to the rather sleazy-looking individual in the back of the courtroom and asked whether or not there were drugs in bed with the two of them when she was arrested. It’s the fact that she is with him.
“And the fact there were drugs is, of course, not prejudicial or not inflammatory in any way. But, to point out to the jury that this woman, who is a married woman, was in bed with this guy, I think that that is prejudicial.
“I’m not going to grant the mistrial, and the reason is this, number one, I don’t think that it was so prejudicial that it creates a situation where the defendant cannot get a fair trial.
“Secondly, and I guess they’re tied together, one of [the] major reasons I feel that way is because defense counsel from the very beginning, even from the time of voir dire, told the jury that this woman used drugs, number one, number two, that she lived with some man not her husband, and asked that the jury *857members, if they were going to hold that against her. I think from that moment on these jury members expected to hear that. It was something brought up by defense counsel originally, not by the prosecution.”
In response defense counsel asserted:
“In voir dire I did ask the jury a question about whether they would hold anything against my client if it was shown that she was living in the same house with another man.
“My reason for asking those questions was that she was living in a house with Gus Skurdal, and I don’t think there was any evidence about any kind of male-female relationship between Gus Skurdal and Tammy Burke. And I just wanted to make sure that the jury didn’t think poorly of my client simply for living with Gus Skurdal. I in no way envisioned the bringing up of the fact that she was arrested in bed with another man. That wasn’t my purpose.”
Appellant now argues that the prosecutor’s conduct denied her a fair trial and that the trial court erred in declining to declare a mistrial. In considering a claim of prosecutorial misconduct, we must review the entire record to determine whether the prosecutor’s conduct resulted in substantial prejudice amounting to the denial of a fair trial. Lindsey v. State, Wyo., 725 P.2d 649 (1986). In reviewing the record, we must evaluate the state of the evidence and the probability of prejudicial impact on the defendant under the circumstances of the particular case. Stogner v. State, Wyo., 674 P.2d 1298, 1302 (1984). Appropriate objections and subsequent curative instructions may cure any error. Lindsey v. State, supra.
We agree with the trial court that the conduct of the prosecutor was highly improper. Viewing the record as a whole, however, we cannot conclude that the prosecutor’s misconduct deprived appellant of a fair trial. During voir dire the jury members indicated that they would not tend to convict appellant because she lived with a male roommate to whom she was not married or because that male roommate was dealing drugs. When the prosecutor asked the improper question, appellant had already admitted that she used methamphetamine. In addition, after the prosecutor asked the question and before appellant answered it, the trial court instructed the jury in no uncertain terms that they should disregard the prosecutor’s question. We must assume that the jury followed the court’s curative instruction. Madrid v. State, Wyo., 592 P.2d 709 (1979); Simms v. State, Wyo., 492 P.2d 516, cert. denied 409 U.S. 886, 93 S.Ct. 104, 34 L.Ed.2d 142 (1972). Appellant has failed to demonstrate substantial prejudice. We conclude that the prosecutor’s conduct did not deny appellant a fair trial.
COSTS OF PROSECUTION
On each count appellant was sentenced to one to two and one-half years in the Wyoming State Women’s Center and assessed a $500 fine. The trial judge suspended all but 28 days of the sentence of incarceration, gave appellant credit for 28 days previously served, and placed appellant on probation for a period of five years, subject to numerous conditions, one of which required that appellant
“[p]ay court costs, for transportation of witnesses, for which the court specifically finds that there was not a justiciable issue concerning chain of custody and laboratory results, and the court specially finds the amount of those costs to be five hundred thirty-two dollars sixty-two cents ($532.62).”
During the sentencing hearing the trial court referred to the costs assessed for transportation of witnesses as “costs of prosecution.” Appellant asserts that the trial court improperly required her to pay costs of prosecution as part of her sentence. We agree. In order to explain our conclusion, we find it necessary to examine in some detail the relevant statutes as they existed at the time when appellant was sentenced.
It is well established that a court cannot tax costs in a criminal case without express statutory authority. Bernard v. State, Wyo., 652 P.2d 982 (1982). At the *858time appellant was sentenced, authority for the assessment of costs of prosecution in misdemeanor cases was found in § 7-11-516, W.S.1977, which provided that when a defendant was convicted of a misdemeanor,
“the punishment shall be within the discretion of the court, limited as penalties now are by law, except that payment of the costs of prosecution may be added to and made a part of the sentence * * *.”
The statute clearly allows such costs to be incorporated into the convicted misdemean-ant’s sentence.
When appellant was sentenced, there was no similar statute dealing with felonies. Prior to the revision of the criminal code in 1983, § 6-1-105, W.S.1977, provided:
“Within the limits prescribed by law, the court shall determine and fix the punishment for any felony or misdemeanor, whether the punishment consists of imprisonment, or fine, or both, and when any person is sentenced to imprisonment in the penitentiary, the court shall declare in its sentence, for what period he shall be imprisoned; and in all cases of a conviction of an offense, the court shall render judgment against the defendant for the costs of prosecution.”
A careful reading of this statute reveals that it required a sentencing judge to “render judgment” for costs of prosecution in both misdemeanor and felony cases; but, unlike § 7-11-516, it did not state that the payment of such costs may be “added to and made a part of the sentence.” In any event, § 6-1-105 was amended. In the revised criminal code, effective July 1, 1983, the corresponding statute appears as § 6-10-104, W.S.1977, which reads:
“Within the limits prescribed by law, the court shall determine and fix the punishment for any felony or misdemeanor, whether the punishment consists of imprisonment, or fine, or both.”
Thus, the legislature deleted the provision permitting judgment for the costs of prosecution in felony cases. As a result, the criminal code provided no authority for assessing costs of prosecution against appellant.3
The Code of Civil Procedure contains limited authority for the assessment of costs of prosecution in criminal cases. Section 1-14-102, W.S.1977, permits the trial court in a criminal case to assess expert witness fees as costs against any party “in the discretion of the court.” Absent a statutory provision to the contrary, however, liability for such costs is in the nature of a civil debt enforced by means of judgment and execution. The Code of Civil Procedure provides no authority for the assessment of costs as part of a criminal sentence or as a condition of probation.
The State contends that § 7-l-112(c) of the Public Defender Act permits the assessment of costs of prosecution as a condition of probation. That section provides:
“(c) To the extent that a person covered by W.S. 7-9.20 [§ 7-1-110] is able to provide for an attorney, the other necessary services and facilities of representation, and court costs, the court may order him to provide for their payment.”
The Public Defender Act does not define the term “court costs” or specify the manner in which the court’s assessment of costs is to be enforced. In our view, however, the 1983 amendment to § 6-1-105, represented a legislative determination that an assessment of costs of prosecution should not be a part of the sentencing procedure in felony cases; and nothing in the Public Defender Act, as it then existed, mandates a contrary conclusion.
The State contends also that even without express statutory authority, a trial judge may assess costs of prosecution as a condition of probation under the broad discretion granted by § 7-13-303, W.S.1977, Cum.Supp.1986.4 In Lansing v. State, *859Wyo., 669 P.2d 923, 927 (1983), we held that “[sentencing judges have wide discretion in determining appropriate conditions of probation.” Such discretion, however, is not unlimited; it must be exercised within the confines of the authority granted by the legislature. See Hicklin v. State, Wyo., 535 P.2d 743, 79 A.L.R.3d 1050 (1975). Because the legislature, in enacting § 6-10-104, W.S.1977, supra, specifically deleted the language permitting assessment of costs of prosecution, we hold that the trial judge exceeded his authority by assessing costs of prosecution as a condition of appellant’s probation.
ASSESSMENT OF ATTORNEY FEES UNDER THE PUBLIC DEFENDER ACT
As a separate condition of probation, the trial court ordered appellant to “reimburse” the State and Campbell County for services provided by the court-appointed public defender. The following provisions of the Wyoming Public Defender Act, as it existed when appellant was sentenced, addressed the subject of payment and reimbursement of attorney fees by indigent defendants:
“Section 7-1-110. Right to attorney; cost; other rights.
“(a) A needy person who is being detained by a law enforcement officer, or who is under formal charge of having committed, or is being detained under a conviction of, a serious crime, is entitled:
“(i) To be represented by an attorney to the same extent as a person having his own counsel if so entitled; and
“(ii) To be provided with the necessary services and facilities of representation (including investigation and other preparation).
“(b) The attorney, services and facilities, and court costs shall be provided at public expense to the extent that the person, at the time the court determines need, is unable to provide for their payment.”
“Section 7-1-112. Determination of needy person.
“(a) Determination of whether a person covered by W.S. 7-9.20 [§ 7-1-110] is a needy person shall be deferred until his first appearance in court or in a suit for payment or reimbursement under W.S. 7-9.24 [§ 7-1-114], whichever occurs earlier. Thereafter, the court concerned shall determine, with respect to each proceeding, whether he is a needy person.
* # # * # #
“(c) To the extent that a person covered by W.S. 7-9.20 [§ 7-1-110] is able to provide for an attorney, the other necessary services and facilities or representation, and court costs, the court may order him to provide for their payment.”
“Section 7-1-114. Recovery of payment,
“(a) The attorney general may, by suit within six (6) years after the date the services were rendered, on behalf of the state, recover payment or reimbursement, as the case may be, from each person who has received legal assistance or another benefit under this act:
“(i) To which he was not entitled;
“(ii) With respect to which he was not a needy person when he received it; or
"(in) With respect to which he has failed to make the certification required by W.S. 7-9.22(b) [§ 7-l-112(b)].
“(b) Amount recovered under this section shall be paid into the state general fund.”
The quoted provisions clearly indicate that those persons who seek assistance under the Act may be required to pay for services and costs to the extent that they are able to pay at the time assistance is requested. This requirement may be enforced by court order at the time the court determines need. The need referred to is need at the time assistance is requested. Such need may be determined either at the defendant’s “first appearance,” some later time, or in a suit by the State under § 7-1-114. At appellant’s arraignment the trial court ordered appellant to “repay the state for *860the costs of the public defender at the rate of $50 per month.” The question we face is whether this order was improperly incorporated into appellant’s sentence as a condition of probation.
When appellant was sentenced, the Public Defender Act contained its own enforcement provisions, none of which contemplated criminal sanctions for noncompliance.5 As we interpret the Act as it then existed, any liability for payment or reimbursement constituted a civil debt; and an order entered pursuant to the Act was not a proper element of the sentencing proceeding. We hold that the district court erred by requiring appellant to reimburse the State for the services of her public defender as a condition of her probation.
Affirmed as modified.
. Under the Wyoming controlled substances conspiracy statute, proof of an overt act is not required. Section 35-7-1042, W.S.1977; Apodaca v. State, Wyo., 627 P.2d 1023 (1981). The difference between the general conspiracy statute and the controlled substances conspiracy statute raises an issue as to whether a trial judge, in making a ruling on the admissibility of a co-conspirator’s statement in a drug prosecution, should require the State to prove an overt act. Because the parties have not raised this issue, and the overt-act element is satisfied in the present case, we need not decide the issue.
. "[MR. WEERTS:] As I remember the situation, Mr. Murray turned himself around, pointed to my client’s boyfriend, who was sitting in the back of the courtroom. He has long hair, he is dressed in a T shirt and a vest, and pretty much. I’d say, looks like a hippie or a motorcycle fellow or something on that order, points to him and asks my client about being arrested with this man while she’s in bed with him.
“And, as I understand it, Mr. Murray’s reason for doing that was cross-examination as to whether she knew anyone in her house over a period of time and whether that person ever had drugs in the house.
“I think that it’s clear that the real reason for Mr. Murray doing what he did was to prejudice the jury against my client, and it’s God awful as far as prejudice.”
. Such authority is now found in § 7-11-505, W.S.1977, enacted in 1987, which provides:
"Payment of the costs of prosecution may be added to and made a part of the sentence in any felony or misdemeanor case.”
. Section 7-13-303, W.S.1977, Cum.Supp.1986, provides:
*859"The court shall determine and may, by order duly entered, impose in its discretion, and may at any time modify any condition of probation or suspension of trial or sentence.”
. Former § 7-1-112, W.S.1977, now appears as § 7-6-106, W.S.1977, and contains the following provision:
“If the court orders probation before sentence, suspended sentence or probation, the court shall order the needy person as a condition of sentence or probation to repay the state for expenses and services provided by appointed attorneys pursuant to the state public defender’s standard fee schedule."