Delbert C. Mitter appeals his felony convictions of sexual abuse in the first degree and misdemeanor convictions of sexual abuse in the third degree which were entered in the Circuit Court of Preston County. His primary assignment of error is that the trial court permitted an expert witness to testify that the acts committed by Mitter were done for sexual gratification which is one of the key elements in a sexual abuse charge.1 Other errors alleged are the trial court’s failure to grant a severance and the insufficiency of the State’s proof in the felony cases because of the failure to prove Mitter’s age as alleged in the indictment.
I.
Mitter was accused of ordering his five stepdaughters to disrobe and rubbing a corncob on which an astringent liniment had been applied between their legs and on their genital areas. Prior to this incident, he had whipped the girls for disobeying him and it was the bruises on the backs of their legs that prompted school authorities to contact a social worker. This action ultimately led to Mitter’s arrest on the sexual abuse charges. At trial, he and his wife denied that the incident ever occurred.
It is clear from the trial record that the testimony of the State’s expert witness was elicited primarily so that he might give his opinion that the defendant’s actions were a form of sexual gratification. The expert, a psychologist, had not interviewed any of the parties to the incident, but *534gave his opinion based on a hypothetical question which covered the facts surrounding the rubbing incident.2 The psychologist testified that the motivation “would be most likely to be both sexual and sadistic in content....”
The general theory which permits an expert witness to give an opinion is that the questions presented are of such a technical nature that persons of ordinary intelligence would not possess the expertise to competently pass judgment thereon. Consequently, it is permissible for experts to assist the jury in these situations as we stated in Syllabus Point 5, Norfolk & Western Railway Co. v. Christian, 83 W. Va. 701, 99 S.E. 13 (1919):
“Opinion evidence of competent experts may be properly called for when the questions presented are of such a nature that persons generally would not be as competent to pass judgment thereon as such experts.”
See also, State v. Noe, 160 W. Va. 10, 230 S.E.2d 826, 830 (1976); Moore v. Shannondale, Inc., 152 W. Va. 549, 165 S.E.2d 113 (1968).
When, however, the subjects being inquired into are within the common knowledge of the jury, expert opinion is ordinarily not admissible. We have expressed this rule in Syllabus Point 7 of Lawrence’s Adm’r v. Hyde, 77 W. Va. 639, 88 S.E. 45 (1916):
*535“Expert opinion evidence concerning a matter as to which the jury are as competent to form an accurate opinion as the witness, is inadmissible.”
See also, Syllabus Point 2, Thrasher v. Amere Gas Utilities Co., 138 W. Va. 166, 75 S.E.2d 376 (1953), dismissed, 347 U.S. 910, 74 S.Ct. 478, 98 L.Ed. 1067 (1954); 31 Am.Jur.2d Expert and Opinion Evidence § 21 (1967). This rule is based on the general premise that to permit such testimony invades the province of the jury which is the ultimate fact finder.
Related to the “common knowledge” prohibition against expert testimony is the rule that an expert should not give an opinion on an ultimate issue in the case as it is thought this also invades the province of the jury. 31 Am.Jur.2d Expert and Opinion Evidence § 22 (1967); Annot., 38 A.L.R.2d 50 (1950). The precise contours of this rule are often difficult to define and some jurisdictions have retreated from the “ultimate issue” rule.3 E.g., State v. Ellis, 89 N.M. 194, 548 P.2d 1212 (1976); State v. Breen, 250 Or. 474, 443 P.2d 624 (1968); State v. Spry, 87 S.D. 318, 207 N.W.2d 504 (1973), overruled on other grounds, 90 S.D. 198, 240 N.W.2d 84 (1976); McCormick on Evidence § 12 (1972 ed.).
As in many matters concerning the rules of evidence, if the inquiry is narrowed to particular evidentiary facts, a more general harmony emerges from what initially appeared to be a variance in opinion. Here, we deal with evidence which was introduced to prove a subjective fact which is an element of intent — whether the defendant’s act was done “for the purpose of gratifying [his] sexual *536desire.” W. Va. Code, 61-8B-116.4 Our examination of cases in this area indicates that the general rule is that expert opinion cannot be offered as to the subjective intent of an individual.
In State v. Hull, 45 W. Va. 767, 32 S.E. 240 (1899), we held it was error for a physician who had examined a rape victim to give his opinion regarding whether she voluntarily submitted at the time of the incident.5 A more analogous case is Koester v. Commonwealth, 449 S.W.2d 213 (Ky. 1969), where it was held that it was proper to exclude a psychiatrist’s opinion in a rape case that the defendant did not have any specific intent to have carnal knowledge. Similar results have been reached in other situations involving the offer of psychiatrists’ opinion testimony concerning a defendant’s mental state with the exception of the issue of insanity.6 E.g., State v. Griffith, 101 Idaho 163, 610 P.2d 522 (1980), expert precluded from testifying defendant was in fear at time of shooting; State v. Matthews, 301 Minn. 133, 221 N.W.2d 563 (1974), expert precluded from giving opinion that defendant was in fear at time he killed victim; Wage v. Commonwealth, 219 Va. 683, 251 S.E.2d 202 (1979), cert. denied, 442 U.S. 924, 99 S.Ct. 2850, 61 L.Ed.2d 292, expert could not testify that defend*537ant lacked requisite malice and premeditation to kill. See also, State v. Zimmer, 198 Kan. 479, 426 P.2d 267 (1967), expert could not offer opinion as to whether defendant had done killing; Commonwealth v. O’Searo, 466 Pa. 224, 352 A.2d 30 (1976), psychiatrist could not give an opinion that defendant was testifying truthfully; Coppola v. Commonwealth, 220 Va. 243, 257 S.E.2d 797 (1979), cert. denied, 444 U.S. 1103, 100 S.Ct. 1069, 62 L.Ed.2d 788, (1980), psychiatrist could not testify that testimony of State’s witness could not be believed.7
One of the difficult problems that arises from permitting an expert to testify about the intent of the defendant independent of the insanity issue is that criminal intent is an indispensable element of almost every area of our criminal law. As we have previously noted in this case, the term “sexual gratification,” which is a required element of sexual abuse, is a subjective state of mind similar to the criminal intent required in other crimes. To permit experts to give opinion testimony, based on hypothetical questions, or based on their examination of the party, on the ultimate issue of criminal intent would, in our view, only serve to unduly confuse and complicate the trial of criminal cases.8 Each side would have the right to offer opinion testimony on the intent or mental state of a defendent. Moreover, in cases where the crime relates in some manner to the mental state of the victim, this will also be the subject of opinion testimony.9 Because these *538intent issues are subjective in nature, it can be expected that the experts will disagree. The consequence will be that the subjective area of intent will no longer be tested by the objective actions and circumstances surrounding the conduct of the party but will be overlayed by varying opinions of experts.
In the final analysis, we believe that such issues are matters which the average juror can understand from the facts surrounding the defendant’s conduct at the time the crime was committed based on his own common sense view of human affairs. Much the same point was made in Collins v. Dravo Contracting Co., 114 W. Va. 229, 235, 171 S.E. 757, 759 (1933), where in speaking of intent, we said:
“In its nature, it is bound to be the existence of a state of mind, and since that state of mind must be arrived at in proof by the establishment of facts extraneous to the mind itself, it seems to us that it is always bound to be a deduction or conclusion from the facts so established.
Again, we stress that we are not dealing here with the insanity issue where expert psychiatric testimony is clearly appropriate. What is involved in this case is the introduction into evidence of the conclusion of an expert on the subjective mental condition of the defendant, i.e. his sexual gratification, which is a key element of the crime of sexual abuse. We conclude that such evidence was improperly admitted and constitutes reversible error.
II.
The defendant objected at trial to the court’s joinder of the five indictments and moved for a severance. The court concluded that joinder was proper based upon Syllabus Point 2 of State ex rel. Johnson v. Hamilton, _ W. Va. _, 266 S.E.2d 125 (1980), overruled on other grounds, _ W. Va. _, 274 S.E.2d 440, part of which states:
“Appropriate protection against multiple trials for offenses arising from the same criminal transaction requires, in future cases, joinder for trial at the same time of all counts arising out of the same transaction either in a single indictment with *539multiple counts or multiple separate indictments;
In the remaining portion of Syllabus Point 2 of Johnson, as well as in the opinion, we suggested that this right of consolidation or joinder of offenses for trial arose because of double jeopardy considerations.10 In our later case of State ex rel. Watson v. Ferguson, _ W. Va. _, 274 S.E.2d 440 (1980), we determined that the double jeopardy basis for joinder of offenses was too broad a principle and established a procedural joinder rule in Syllabus Point 1, as follows:
“A defendant shall be charged in the same indictment, in a separate count for each offense, if the offenses charged, whether felonies or misdemeanors or both, are of the same or similar character, or are based on the same act or transactions, or are two or more acts or transactions connected together or constituting parts of a common scheme or plan.”
We also made it clear in State ex rel. Watson v. Ferguson, supra, that we disapproved of State ex rel. Johnson v. Hamilton, supra, to the extent it “set the rule as a constitutional holding....” 274 S.E.2d at 444. The procedural joinder rule in Watson parallels Rule 8(a) of our new Rules of Criminal Procedure, which became effective Oc*540tober 1, 1981.11 This same general joinder rule has been our law by virtue of case law and statutes.12 One of our leading cases on joinder of offenses in a single indictment is State v. LaRue, 98 W. Va. 677, 128 S.E. 116 (1925), where we stated in Syllabus Point 3 and 4:
“3. If all of the offenses charged in one or more counts of an indictment represent but one continuous transaction, it is well settled in this state that they may be so joined as distinct offenses in different counts, and that where properly joined as distinct offenses, unless they appear on the face of the indictment to involve a different transaction, a motion to quash for misjoinder should be overruled.
“4. A joinder as separate counts in one indictment of several offenses, which though distinct in point of law, yet spring out of substantially the same transaction, cannot operate to the legal prejudice of the accused; and he is not entitled as a matter of right in such case to compel an election.”
See also, State v. Koton, 157 W. Va. 558, 202 S.E.2d 823 (1974); State v. Tabet, 136 W. Va. 239, 67 S.E.2d 326 (1951); 9B Michie’s Jurisprudence, Indictments, Informations and Presentments § 42 (1977); Note, Joinder of Crimes in the Same Indictment, 57 W. Va. L. Rev. 196 (1955).
*541The general rule at common law is stated in 1 Wharton, Precedents of Indictments and Pleas p. 31 (1881 ed.):
“Offences, though differing from each other, and varying in the punishments authorized to be inflicted for their perpetration, may be included in the same indictment, and the accused tried upon the several charges at the same time, provided the offences be of the same general character, and provided the mode of trial is the same.”
We have also recognized the necessity of setting separate offenses in different counts of the indictment. State v. Winkler, 142 W. Va. 266, 95 S.E.2d 57 (1957); State v. Wisman, 98 W. Va. 250, 126 S.E. 701 (1925).
We did not have occasion in State ex rel. Watson v. Ferguson, supra, to discuss the question presented here of the right to consolidate separate indictments for purposes of one trial. Research has not disclosed any case where this Court has discussed this point. It is clear from Rule 13 of our Criminal Rules of Procedure, as well as Rule 13 of the Federal Rules of Criminal Procedure, that consolidation of separate indictments is permitted and is governed by the same test that is utilized for the joinder of offenses under Rule 8(a). 1 Wright, Federal Practice and Procedure § 212 (1969). If the offenses are of a same or similar character or arise from the same transaction, joinder is appropriate.13 We have previously noted that our general rules on joinder of offenses essentially followed what is now Rule 8(a) of our Rules of Criminal Procedure. Thus, it is reasonable to apply by analogy the case law relating to joinder of offenses to consolidation of indictments for trial. Other courts have done so in the absence of Rules of *542Criminal Procedure or procedural statutes. See, e.g., Hall v. State, 66 So.2d 863 (Fla. 1953); Wilson v. State, 245 Ga. 49, 262 S.E.2d 810 (1980); State v. Collins, 204 Kan. 55, 460 P.2d 573 (1969); Williams v. State, 214 Md. 143, 132 A.2d 605 (1957); Commonwealth v. Ianello, 344 Mass. 723, 184 N.E.2d 364 (1962); Commonwealth v. Rosenthal, 211 Mass. 50, 97 N.E. 609 (1912); State v. Parrish, 45 Or. App. 99, 607 P.2d 778 (1980); Commonwealth ex rel. Conyers v. Banmiller, 193 Pa. Super. 368, 165 A.2d 278 (1960); Commonwealth v. Crandall, 145 Pa. Super. 353, 21 A.2d 232 (1941), cert. denied, 314 U.S. 686, 62 S.Ct. 296, 86 L.Ed. 549; Annot., 59 A.L.R.2d 835 (1958); 53 Am.Jur. Trial § 67 (1945).
Thus, we conclude that a trial court may in its discretion order two or more indictments, or informations, or both, to be tried together if the offenses could have been joined in a single indictment or information, that is, the offenses are of the same or similar character or are based on the same act or transaction, or on two or more acts or transactions connected together or constituting a common scheme or plan.
The question of whether a defendant is entitled to obtain a severance where there has been a joinder of different offenses in the same indictment or a consolidation of different indictments for the purpose of one trial depends on several circumstances. In those situations where the offenses charged are interrelated and the prosecutor joins offenses because he is unsure which offense he will be able to prove at trial, severance is not warranted.14
*543However, where there are separate offenses arising out of the same transaction, there may be some instances when a defendant’s motion for severance should be granted. Our law in this area is not very illuminating since we have failed in the past to distinguish between cases where separate counts are used to cover closely related offenses where the proof is not clear as to which offense has been committed, and those where there are distinct offenses which have occurred as a part of the same transaction. See, State v. Carter, _ W. Va. _, 282 S.E.2d 277, 281 n. 4 (1981).
The reason there has not been much discussion in our case law concerning severance may be due to the fact that it was not until State ex rel. Johnson v. Hamilton, supra, that this Court suggested that offenses arising from the same criminal transaction had to be tried in a single trial. Previously, the matter of joinder was left to the option of the prosecutor. The defendant then had the right to attack the joinder through a motion to quash the indictment because of misjoinder or duplicity. 1 Lee, Criminal Trials in the Virginias §§ 30-35 §§ 81-84 (1940 ed.).15
Courts that have addressed the problem have recognized that joinder or consolidation may prejudice the defendant because the jury may tend to cumulate the evidence of the various offenses and convict the defendant on all offenses charged on the theory he is a bad individual rather than weigh the evidence separately on each offense. From the defense standpoint, trial on multiple offenses may make it difficult to establish separate defenses to individual charges. Furthermore, it may inhibit the defendant’s ability to testify on his own behalf if he wishes to testify about some of the charges but not about others. Cross v. United States, 335 F.2d 987 (D.C. App. 1964); Drew v. United States, 331 F.2d 85 (D.C. App. 1964); 1 Wright, Federal Practice and Procedure § 222 (1969). See *544also, Meade v. State, 85 So.2d 613 (Fla. 1956); Hadjis v. Iowa Dist. Court of Linn County, 275 N.W.2d 763 (Iowa 1979); Commonwealth v. Slavski, 245 Mass. 405, 140 N.E. 465 (1926); Commonwealth v. Tracey, 137 Pa. Super. 221, 8 A.2d 622 (1939); Annot., 59 A.L.R.2d 835 (1958); 53 Am.Jur. Trial § 67 (1945).
We have previously stated that the joinder of related offenses to meet possible variance in the evidence is not ordinarily subject to a severance motion. In those other situations where there has been either a joinder of separate offenses in the same indictment or the consolidation of separate indictments for the purpose of holding a single trial, the question of whether to grant a motion for severance rests in the sound discretion of the trial court.
In the present case, we do not find that the trial court erred in refusing separate trials on these related offenses. Defendant’s defense was essentially the same to all charges: that he did not commit the offenses. This case was not one where the defendant could argue that the State’s proof was so minimal on a given charge that to permit it to be tried with other charges would result in bolstering the weak charge. Finally, there was no contention made that the defendant desired to testify on some of the charges and not others.16
Because of the impermissible testimony of the State’s expert witness, we conclude that this case must be reversed and a new trial awarded. Such testimony went to a critical element of the State’s case and cannot be deemed harmless error under State v. Adkins, 162 W. Va. 815, 261 S.E.2d 55 (1979), cert. denied, 445 U.S. 904, 100 S.Ct. 1081, 63 L.Ed.2d 320 (1980). The judgment of the circuit court is *545therefore reversed and the case is remanded for a new trial.
Reversed and Remanded.