*615OPINION
By the Court,
Agosti, J.:Real party in interest Robert Romano is charged in an indictment with four counts of sexual assault of a minor under fourteen years of age and ten counts of lewdness with a child under fourteen years of age. The district court granted Romano’s motion to compel the child victim to submit to an independent psychological examination. The State requests that this court issue a writ of prohibition, or in the alternative, mandamus, to prevent the Eighth Judicial District Court from enforcing its May 5 , 2003, order granting Romano’s motion for an independent psychological examination of the victim.
FACTS
Robert Romano and his girlfriend are the natural parents of the child victim, born May 5, 1997. The couple and their child lived together in an apartment in Las Vegas until the couple’s relationship began to deteriorate and the mother moved out. In August or September 2002, Romano moved into a house in North Las Vegas. Romano and the mother agreed that the child would reside with Romano during the week so that the child could attend a better school. Romano claims that the mother asked him to take the child full time because she was not capable of taking care of the *616child and wanted the child to live in a better neighborhood. Romano claims that, due to the mother’s job as a stripper, she rarely visited the child.
Romano also claims that shortly after his move, the mother informed him that she had obtained stable employment as a waitress, was ready to assume more parental responsibilities and wanted the child to reside with her. Romano refused the mother’s request because he felt the child had become accustomed to his home, neighborhood and school. Romano states that as a result of his refusal a custody dispute ensued.
In November 2002, the child allegedly told her mother that Romano had engaged in inappropriate activities with her. The mother contacted Nevada Child Protective Services and, at that agency’s request, took the child to Sunrise Hospital for evaluation. Doctor Harold Zilberman, a pediatric emergency physician at Sunrise, testified before the grand jury that the findings of the child’s examination were normal, meaning that there were no signs of trauma, but that this did not necessarily preclude the possibility of sexual assault.
On December 19, 2002, the five-year-old child testified before the grand jury that she knew people were not supposed to touch certain areas of her body. She testified that she had touched Romano’s “ding-ding” with her hands. She also demonstrated how she touched him and that, when she did, “lotion” came out of the hole. The child also stated that her father put his “ding-ding” in her mouth. This activity occurred both at the apartment shared by her parents and later at her father’s house. The child testified that Romano had touched her butt with his hands and mouth while they were both naked and that he told her not to tell anyone. The child’s mother was not present in the courtroom when the child testified.
The mother testified to the grand jury that she was not fabricating or lying to get Romano in trouble. She testified that she did not seek a change in custody until the child had told her about Romano’s behavior. Romano did not testify before the grand jury. Instead, he requested that the prosecutor tell the grand jury that the mother had
fabricated these charges and used the child either for financial gain or to get revenge on Robert Romano because she thought Robert Romano was going to bring child custody proceedings to take the child away from her because of her unfitness as a mother and her physical abuse of the child.
Detective Jay Roberts also testified before the grand jury concerning his interview with Romano. Detective Roberts testified that initially Romano denied all the allegations and stated that he had *617never showered or bathed with the child. Romano insisted that the child’s mother had coached the child and that the mother exposed the child to sex movies. Romano also told Detective Roberts that the child strikes sexy poses like Britney Spears. As the interview progressed, however, Romano admitted bathing with the child and sleeping in the same bed while both were clothed. Romano also told the detective that, on several occasions when he was on the computer, the child had reached into his gym shorts and grabbed him. Detective Roberts testified that Romano then admitted that the child had probably grabbed his penis in the shower when they lived in the apartment. Romano also related to Detective Roberts that the child had once caught him masturbating in the bathroom and that that is where she had seen the “lotion.”
Detective Roberts further testified that, when he asked Romano why the child had told the detective that her father put his mouth on her “peck-peck,” the child’s term for vagina, Romano stated that he had to sniff her vagina after she bathed to make sure she was clean, and that perhaps his nose or moustache accidentally touched the child. He said that the child’s mother made him do it. Romano told the detective that the child had also told him to kiss her “peck-peck” and her butt.
On January 10, 2003, the grand jury returned a true bill and Romano was then indicted on four counts of sexual assault of a minor under fourteen years of age and ten counts of lewdness with a child under fourteen years of age. On April 10, 2003, Romano moved for an independent psychological examination of the victim, alleging that there was no corroborating evidence other than the victim’s testimony and that a reasonable basis existed for believing the victim’s mental or emotional state may have affected her veracity. The district court granted Romano’s motion and the State thereafter filed, with this court, a petition for a writ of prohibition or, alternatively, for a writ of mandamus.
DISCUSSION
Writ relief
We first consider whether a petition for writ relief seeking either to prevent the district court from enforcing its order or compelling it to vacate its order is proper in the instant case. Both mandamus and prohibition are extraordinary remedies, and are only appropriate when a plain, speedy and adequate remedy at law is not available.2 “A writ of mandamus is available to compel the performance of an act which the law requires as a duty resulting from an office, *618trust or station, NRS 34.160 . . . ,”3 A “writ of prohibition is the counterpart of the writ of mandate” and is available to halt a tribunal’s proceedings “when such proceedings are without or in excess of the jurisdiction of such tribunal.’ ’4 Petitions for extraordinary relief are not meant to control discretionary acts, ‘ ‘ ‘unless discretion is manifestly abused or is exercised arbitrarily or capriciously.’ ”5 Finally, whether to grant the extraordinary remedy of writ relief is within the court’s sound discretion.6
The instant petition follows the district court’s order compelling an independent psychological examination of the victim. We have previously held that writ relief is available to prevent improper discovery.7 Moreover, we have held that “prohibition is a more appropriate remedy for the prevention of improper discovery than mandamus.”8
In the instant case, a plain, speedy and adequate remedy at law is not available to the State. If improper discovery proceeds, this young alleged sexual assault victim will be unnecessarily subjected to an intrusive examination and the State will have no effective remedy to cure the improper discovery. Delayed consideration of this procedural issue until after completion of the trial will irreparably intrude upon the minor child’s privacy rights. Under this circumstance, we consider entertainment of writ relief necessary. Accordingly, we conclude that the State’s petition for a writ of prohibition is the appropriate vehicle for challenging the order compelling a psychological examination of the minor child.
Jurisdiction of trial courts
Because the Nevada Constitution does not grant a right to discovery in a criminal case or a right to order an alleged sexual assault victim to submit to psychological examination, the State suggests that we must find authority for such an examination in either statutory law or common law.9
*619 Statutory authority
The State argues that the closest statutory sources empowering the trial court to order an alleged sexual assault victim to submit to a psychological examination are NRS 174.235 and NRCP 35, but that neither the statute nor the rule grants sufficient authority to the trial courts.
Although NRS 174.235 codifies discovery powers in criminal cases, the ability to discover reports of mental examinations of an alleged victim is limited to reports within the State’s possession. NRS 174.235 does not grant trial courts the authority to require an alleged victim, who is, after all, a witness in the action but not a party to the action, to submit to psychological examination. NRCP 35 authorizes a trial court to order a party in a civil suit to submit to a mental examination when the mental condition of that party is in controversy. However, this authority cannot be extended to the criminal arena because, in a criminal case, the complaining witness is not a party to the action. We observe, therefore, that no statutory authority exists for trial courts to order a psychological examination of a complaining witness in a criminal prosecution for sexual assault.
Common-law authority
The judiciary is inherently vested with the power to promulgate its own rules of procedure when “ ‘necessary or desirable to handle the business of the courts or their judicial functions,”’10 or “when necessary in the interests of justice.”11 Because the psychological examination of a victim “could be crucial to the truth-seeking process,”12 we have, in the past, concluded that a trial court may order a sexual assault victim to submit to a psychological examination under certain limited circumstances.
In Washington v. State,13 we stated that trial courts have discretionary authority to order the psychological examination of a sexual assault victim. In support of our conclusion, we cited case law from Arizona and California: State v. Jerousek14 and Ballard v. *620Superior Court of San Diego County.15 In those cases, those courts empowered the trial courts with discretionary authority to order a sexual assault victim to submit to psychological examination. Jerousek, while still the law in Arizona, relied heavily on Ballard,16 which has since been superseded by California Penal Code § 1112.17 The Ballard court had articulated antiquated beliefs that women falsely accuse men of sex crimes “as a result of a mental condition that transforms into fantasy a wishful biological urge,” from aggressive tendencies directed to the accused or from “a childish desire for notoriety.”18 In overruling Ballard, in 1986, the California Supreme Court acknowledged that “previous expectational disparities, which singled out the credibility of rape complainants as suspect, have no place in a modern system of jurisprudence.”19
While we relied on the holding in Ballard for our decision in Washington, we failed to discuss our reasoning for granting trial courts the discretionary authority to order psychological examination of an alleged sexual assault victim. Nor do our decisions subsequent to Washington clarify our reasoning.20 Although we unequivocally disapprove of the antiquated beliefs concerning women mentioned in Ballard, we reaffirm our holding that a trial court has the discretion to order alleged victims to submit to psychological examination under certain narrow circumstances. To clarify, we now revisit this issue.
The State first argues that compelling a sexual assault victim to submit to psychological examination may lead to greater embarrassment and humiliation than the victim has already suffered, directly in contravention of public policy. The State asserts that sex*621ual assault victims encounter a number of hardships within the state criminal system,21 including most significantly, confronting the attacker in court, testifying regarding personal details of the sexual assault in open court and possibly being subjected to aggressive, detailed and humiliating cross-examination by the defense.22 The State emphasizes that the Nevada Legislature has also recognized that victims of sexual assault need protection and that the State has a compelling interest in encouraging victims of sexual assault to report crimes, to cooperate with the State’s investigation and to testify at trial.23 Additionally, the State notes that the Legislature’s adoption of the rape shield law, NRS 50.090, indicates its concern for the privacy rights of sexual assault victims.24 Finally, the State cautions that there are currently no guidelines to protect victims who are ordered to submit to psychological testing.25
The State also asserts that, in nonsexual assault cases, defendants do not have the ability to force an alleged victim or any other witness to submit to psychological testing. This discovery tactic has been limited to sexual assault victims. The State argues that, as in nonsexual assault cases, traditional methods of assessing a witness’s credibility, such as cross-examination of the victim, presentation of defense expert witnesses regarding the victim’s ability to relay the truth and appropriate jury instructions concerning credibility,26 are adequate to allow the fact-finder to address the question *622of the alleged sexual assault victim’s truthfulness.27 Finally, the State submits that ordering an alleged victim to submit to psychological testing for the purpose of determining credibility undermines the role of the jury.
Addressing the State’s arguments concerning the role of the jury, an expert may testify that symptoms exhibited by the victim are consistent with those normally attributable to certain traumatic events.28 This is true even though the opinion testimony embraces an ultimate issue in the case.29 However, an expert’s bolstering of a witness and an expert’s direct opinion concerning the victim’s credibility or veracity are both inadmissible.30 Assessing the credibility of witnesses and weighing the evidence are functions of the jury.31 Accordingly, to allow any expert, whether the State’s or the defendant’s, to testify as to an opinion of the truthfulness of a victim or witness, impermissibly invades the province of the jury.32
Furthermore, while we recognize that a fixed rule or a rule giving trial courts unbridled discretion may subject a victim to unnecessary harassment and embarrassment, we also recognize that a defendant has the right to preserve his constitutional right to a fair trial by countering the State’s proffered evidence. In Koerschner v. State,33 we reconciled prior Nevada case law concerning a trial court’s discretionary power to order the psychological examination of a sexual assault victim. We concluded that the overriding judicial question is whether a compelling need exists for the trial court to order a psychological examination.34 In determining whether a compelling need exists, Koerschner requires a trial court to consider three factors, not necessarily to be given equal weight: (1) whether the State calls or benefits from a psychological expert, (2) whether little or no corroboration of the offense exists beyond *623the victim’s testimony, and (3) “whether there is a reasonable basis for believing that the victim’s mental or emotional state may have affected his or her veracity.”35
We conclude, however, that the Koerschner test does not always adequately balance the needs of the victim and the defendant. We therefore modify our decision in Koerschner. We now hold that a defendant is entitled to a psychological examination of an alleged sexual assault victim only where: (1) the State notices the defendant that it intends to examine the victim by its own expert and (2) the defendant makes a prima facie showing of a compelling need for a psychological examination. In determining whether a compelling need exists, the trial court must consider: (1) whether little or no corroboration of the offense exists beyond the victim’s testimony, and (2) whether there is a reasonable basis “for believing that the victim’s mental or emotional state may have affected his or her veracity.”36 Moreover, in the exercise of discretion, we require that trial courts set forth a particularized factual finding that there is reason to believe that a psychological examination is warranted.
We further hold that a victim is not required to submit to a psychological examination. Where the victim refuses to submit to an examination, however, we hold that the State may not introduce expert evidence, either in a report or testimony that addresses or assesses the victim’s character.37 “An expert who has personally examined a victim is in a better position to render an opinion than is an expert who has not done so.”38 Therefore, when the victim refuses to submit to a psychological examination by a defendant’s expert, both the State and the defendant would be restricted to the use of generalized testimony submitted by non-examining experts.39
*624Given our recognition of the validity of Washington and its line of authority and applying Koerschner, as modified, to the instant case, we conclude that the district court manifestly abused its discretion when it ordered the psychological examination of the child victim. Because the State has not conducted a psychological examination of the child victim and does not intend to call an examining expert at trial, Romano may not request an independent psychological examination of the victim.
Furthermore, Romano has failed to demonstrate a compelling need for a psychological examination of the child. Romano’s statements to Detective Roberts corroborate the child’s testimony. The record reflects several inconsistencies in Romano’s statements to Detective Roberts and several instances where Romano initially denied an event, then later stated that the event happened, but that it was innocent. Although Romano attempted to explain the innocence of his conduct, we conclude that Detective Roberts’s testimony concerning his interview with Romano corroborated much of the child’s testimony regarding the charges against her father.
Romano’s argument that Detective Roberts was biased is also without merit. Romano argues that the inconsistencies in his statements were a result of a natural tendency “to explain occurrences which, depending upon the bias of the individual considering said occurrences, could be viewed as nefarious in nature.” Romano asserts that Detective Roberts’s bias prevented him from seeing that television programming could have influenced the child to make her statements. Romano argues that it is obvious that sex is pervasive on television and that this could have motivated the child to testify as she did. Romano, however, has failed to demonstrate any causal relationship between the victim’s statements and television programming. Moreover, Romano is unable to refute the evidence that Detective Roberts’s testimony concerning his interview with Romano corroborates the victim’s testimony.
The second consideration is whether Romano demonstrated a reasonable basis to believe that the victim’s mental or emotional state may have affected her veracity. The State asserts that there is nothing in the record suggesting that the child is or was suffering from any kind of mental or emotional state that would affect her ability to be truthful. At the grand jury proceedings, the child did not appear to suffer from memory loss, was not inconsistent in her testimony and was not unsure of her answers.40 Romano first argues *625that the child’s mother coached her daughter because she wants custody of the child. Second, Romano argues that the mother’s previous profession as a stripper inadvertently influenced the child’s testimony. Romano contends that the child may have overheard her mother describing or performing certain acts on the mother’s numerous boyfriends. He contends that, as a result of her mother’s behavior, the child may be under the belief that certain sexual acts are appropriate between those who love each other and simply concocted the story to show her love of her father.
While Romano claims that the mother either coached the child or inadvertently influenced her, he also states that the child stayed with him during the week, and that the mother rarely visited. While Romano states that the mother has a motive to coach her daughter in an attempt to gain custody, the mother testified at the grand jury proceedings that she had no intention of seeking custody until she became aware of Romano’s behavior. Romano has failed to demonstrate otherwise. We therefore conclude that these bare allegations do not call the child’s veracity into question.
Finally, Romano asserts that the media’s broadcast of masturbation and fellatio, acts with which he is also charged, influenced the child’s testimony.41 Romano states that media attention to these sexual acts is prevalent in both television broadcast and print media, including open discussions on talk shows during the afternoon when kids return home from school, and that young children are the recipients of sexually suggestive programming. Romano’s theory that “the television did it” is unconvincing. We conclude that Romano’s request for psychological examination of the child is a mere fishing expedition.42 Accordingly, we conclude that the district court abused its discretion when it determined that a compelling need existed to grant Romano’s motion for an independent psychological examination of the child victim.
CONCLUSION
We conclude that the district court abused its discretion in ordering the child witness to submit to an independent psychological examination by the defendant’s experts. Accordingly, we grant the State’s petition for a writ of prohibition to prevent the district *626court from ordering the child victim to submit to a psychological examination. We direct the clerk of this court to issue a writ of prohibition directing the district court to vacate its order granting Romano’s motion to compel the child victim to submit to a psychological examination.
Shearing, C. J., Becker and Gibbons, JJ., concur.NRS 34.170; NRS 34.330.
Panko v. District Court, 111 Nev. 1522, 1525, 908 P.2d 706, 708 (1995).
NRS 34.320.
State of Nevada v. Dist. Ct. (Anzalone), 118 Nev. 140, 147, 42 P.3d 233, 237-38 (2002) (quoting Round Hill Gen. Imp. Dist. v. Newman, 97 Nev. 601, 604, 637 P.2d 534, 536 (1981)).
Id. at 146, 42 P.3d at 237.
Wardleigh v. District Court, 111 Nev. 345, 350, 891 P.2d 1180, 1183 (1995); Clark v. District Court, 101 Nev. 58, 64, 692 P.2d 512, 516 (1985); Schlatter v. District Court, 93 Nev. 189, 193, 561 P.2d 1342, 1344 (1977).
Wardleigh, 111 Nev. at 350, 891 P.2d at 1183.
State v. Gabrielson, 464 N.W.2d 434, 436-37 (Iowa 1990) (noting that, because a defendant does not have a constitutional right to a psychiatric exami*619nation of a sexual abuse victim to determine the victim’s credibility, a trial court’s authority to order such an examination must be based on statutory or common law).
State v. Dist. Ct., 116 Nev. 953, 959, 11 P.3d 1209, 1213 (2000) (quoting Galloway v. Truesdell, 83 Nev. 13, 23, 20, 422 P.2d 237, 244, 242 (1967) (noting that “any power or authority that is inherent or incidental to a judicial function is properly within the realm of judicial power”)).
Gabrielson, 464 N.W.2d at 437.
Judith Greenberg, Note, Compulsory Psychological Examination in Sexual Offense Cases: Invasion of Privacy or Defendant’s Right? 58 Fordham L. Rev. 1257, 1259-60 (1990).
96 Nev. 305, 307, 608 P.2d 1101, 1102-03 (1980).
590 P.2d 1366 (Ariz. 1979).
410 P.2d 838 (Cal. 1966), superseded by statute as stated in People v. Haskett, 640 P.2d 776, 787 n.7 (Cal. 1982) (noting that a trial court may not order victims to submit to psychological examinations since the legislative enactment of Cal. Penal Code § 1112).
Jerousek, 590 P.2d at 1371.
See Haskett, 640 P.2d at 787 n.7; Cal. Penal Code § 1112 (adopted 1980) (West 2004) (proscribing a trial court from ordering any witness or victim in a sexual assault prosecution to submit to psychological examination for purposes of assessing credibility).
Ballard, 410 P.2d at 846 (stating that the jury should not hear a sex offense charge until a qualified physician testifies as to his examination of the female victim’s mental state and social history).
People v. Barnes, 721 P.2d 110, 121 (Cal. 1986).
See Chapman v. State, 117 Nev. 1, 16 P.3d 432 (2001); Koerschner v. State, 116 Nev. 1111, 13 P.3d 451 (2000) (abrogating Marvelle v. State, 114 Nev. 921, 966 P.2d 151 (1998), and Griego v. State, 111 Nev 444, 893 P.2d 995 (1995), and overruling Keeney v. State, 109 Nev. 220, 850 P.2d 311 (1993)); Lickey v. State, 108 Nev. 191, 827 P.2d 824 (1992); Colley v. State, 98 Nev. 14, 639 P.2d 530 (1982).
Turner v. State, 111 Nev. 403, 404, 892 P.2d 579, 579 (1995) (recognizing that sexual assault victims experience a number of hardships, including: “(1) the initial emotional trauma of submitting to the official investigatory processes; (2) the fear of humiliation attendant to the publicity surrounding a sexual offense charge and embarrassment caused by demeaning defense tactics at trial; and (3) the vicious and discouraging process of ‘blaming the victim,’ whereby the police, the public, and the jury seek to determine whether a potential sexual offense charge was ‘victim-precipitated’ ”).
United States v. Dildy, 39 F.R.D. 340, 343 (D.D.C. 1966).
NRS 200.377(1)-(2).
See Johnson v. State, 113 Nev. 772, 776, 942 P.2d 167, 170 (1997); Lane v. District Court, 104 Nev. 427, 444, 760 P.2d 1245, 1256 (1988).
The State sets forth significant questions, including “whether the victim has a right to counsel during the examination, whether the victim can refuse to answer irrelevant questions about her personal life, [and] whether multiple defendants are entitled to have the victim examined by their own expert.”
See Gilpin v. McCormick, 921 F.2d 928, 932 (9th Cir. 1990) (holding that the trial court’s refusal to order psychological examination of a sexual assault victim did not violate the defendant’s right of confrontation because the Confrontation Clause requires only an opportunity for effective cross-examination). See generally Maryland v. Craig, 497 U.S. 836 (1990) (holding that the state’s interest in the psychological well-being of sexual assault child victims may outweigh a defendant’s right to face his accusers in court).
See United States v. Riley, 657 F.2d 1377, 1387 (8th Cir. 1981) (noting that the ability of the jury to observe and appraise the victim’s credibility safeguards a defendant’s rights).
See NRS 50.345 (“In any prosecution for sexual assault, expert testimony is not inadmissible to show that the victim’s behavior or mental or physical condition is consistent with the behavior or condition of a victim of sexual assault.”).
NRS 50.295.
Marvelle, 114 Nev. at 931, 966 P.2d at 157.
McNair v. State, 108 Nev. 53, 56, 825 P.2d 571, 573 (1992).
Lickey, 108 Nev. at 196, 827 P.2d at 827.
116 Nev. at 1116-17, 13 P.3d at 455 (abrogating Marvelle, 114 Nev. 921, 966 P.2d 151 and Griego, 111 Nev. 444, 893 P.2d 995, and overruling Keeney, 109 Nev. 220, 850 P.2d 311).
Id.
Id. at 1117, 13 P.3d at 455.
Id.; see Greenberg, supra note 12, at 1265 (“[A] defendant has an interest in remaining free of warrantless accusations. This can occur when a victim mistakenly accuses the defendant of a sexual offense, especially where, for example, she suffers from a type of mental defect that renders her unable to distinguish fact from fantasy or when she is a liar.” (footnotes omitted)). But see State v. Tobias, 769 P.2d 868, 869 (Wash. Ct. App. 1989) (stating that “psychiatric testimony would appear to be irrelevant where the complaining witness’s credibility is called into question merely because corroboration of her story is lacking” because a credibility determination is within the jury’s province).
People v. Wheeler, 602 N.E.2d 826, 833 (Ill. 1992).
Id. at 832.
See id. at 833.
See Koerschner, 116 Nev. at 1117, 13 P.3d at 456 (concluding that, “while the child-victim . . . had experienced a very tragic and stressful childhood, there was no indication in the record that her veracity was affected to any particular degree by her mental or emotional state”); cf. Marvelle, 114 Nev. at 928, 966 P.2d at 155 (concluding victim’s veracity was called into *625question where she took four years to tell her story, statements accusing defendant were similar to her confessions to friends that someone else had molested her and there was testimony that the victim would often lie); Griego, 111 Nev. at 451, 893 P.2d at 1000 (concluding that the victim’s veracity was called into question when he could not remember whether the testimony was his or someone else’s).
Romano makes this assertion in spite of his disclosure to Detective Roberts that the child had seen him masturbating several times.
State v. Welch, 490 N.W.2d 216, 219 (Neb. 1992).