Driscoll claims sec. 944.11 (1) and (2), Stats., is unconstitutional because of vagueness and overbreadth. We disagree. The test of vagueness of a penal statute is whether it gives reasonable notice of the prohibited conduct to those who would avoid its penalties. The test of overbreadth is whether the language of the section is so broad as to discourage conduct expressly protected by the constitution, i.e., conduct the state has no right to prohibit. Connelly v. General Construction Co. (1926), 269 U. S. 385, 46 Sup. Ct. 126, 70 L. Ed. 322, is often quoted for the void-for-vagueness rule. Recent cases citing Connelly and noting the distinction between vagueness and overbreadth are Cameron v. Johnson (1968), 390 U. S. 611, 616, 88 Sup. Ct. 1335, 20 L. Ed. 2d 182; Zwickler v. Koota (1967), 389 U. S. 241, 249, 88 Sup. Ct. 391, 19 L. Ed. 2d 444.

Vagueness rests upon the procedural due-process requirement of a fair notice and the defendant cannot *702hypothesize fact situations but is confined to the conduct charged when it is so obviously within the zone of prohibited conduct that no reasonable man could have any doubt of its criminality. Jordan v. De George (1951), 341 U. S. 223, 71 Sup. Ct. 703, 95 L. Ed. 886; Robinson v. United States (1945), 324 U. S. 282, 65 Sup. Ct. 666, 89 L. Ed. 944.

The acts of indecent liberty here involved are fellatio and cunnilingus and there can be no doubt in the minds of reasonable persons that such acts constitute acts of sex perversion and are clearly within the meaning of indecent use and liberty of the sex organs. Consequently, we do not reach the niceties of the hypothetical applications of this section to other acts to test the definition of or the scope of indecent liberties or indecent use or whether actual intention need be an express element of the crime.1

The jury was given the definition of “indecent liberties” found in Wis J I — Criminal 1525, 1527, 1529: “. . . the phrase ‘indecent liberties’ means ‘such liberties as the common sense of society would regard as indecent and improper.’ ” This language is taken from State v. Hoffman, supra, note 1, which analogized the jury’s duty in such case to that of a civil jury with the duty of determining what is reasonable care, reasonable time, or the like. Driscoll argues such a variable standard of guilt renders the statute void for vague*703ness.2 We disagree. In State v. Evjue (1948), 253 Wis. 146, 159, 33 N. W. 2d 305, we held it is not violation of due process for a statute to cast upon the public the duty of care or even of caution, if “there is sufficient warning to one bent on obedience, that he comes near the proscribed area.” While indecent liberties or use is not a slide-rule measurement, we think what the common sense of society regards as indecent or improper to be a sufficiently definite guideline to alert a person bent on obedience.

While it is permissible under the argument of over-breadth which rests on substantive rather than procedural due-process grounds to raise hypothetical examples of the section’s applicability to show that the section deters protected activities, we do not find Driscoll’s example persuasive or valid to establish overbreadth. Only a strained construction of the terms “indecent liberties” or “indecent use” in sec. 944.11 (2) and (3), Stats., would give such a sweep as to be censured for over-breadth. The normal and reasonable meaning of the language must be found so broad that its sanctions *704apply to constitutionally protected conduct which the state is not entitled to regulate before a statute can be faulted for overbreadth. State v. Starks (1971), 51 Wis. 2d 256, 259, 260, 186 N. W. 2d 245.

Driscoll claims error in the admission of inculpatory statements made by him to a social worker at the Southwestern Mental Health Clinic in Lancaster. The social worker had a bachelor’s degree in social work and a master’s in business administration but was neither a physician nor had any medical training. Driscoll and his wife came to the clinic on a self-referral basis on November 25, 1968, and Mrs. Driscoll stated to the social worker that her husband had had relations with her daughter. Driscoll denied such conduct. On a return visit on December 2, 1968, Driscoll again denied such conduct, but on December 3, 1968, Driscoll made a statement to the social worker that he had in fact had relations with the child. Driscoll stated the social worker told him such conferences were confidential. The social worker testified confidentiality was essential to his work and two affidavits were put in evidence at the hearing on the motion to suppress, one from a psychiatrist at the clinic and one from another social worker, stating confidentiality in such conferences was crucial.

Since no action for divorce or legal separation was pending and the conference with the social worker was not at the behest of a family court commissioner, sec. 247.081, Stats., is not applicable.3 While it is argued *705this situation has all the earmarks of a situation which calls for testimonial confidentiality, we cannot give the section such a liberal construction as would change the express language of its scope and applicability. Lukaszewicz v. Concrete Research, Inc. (1969), 43 Wis. 2d 335, 342, 168 N. W. 2d 581.

Nor can we accept the argument that the state is estopped from using the inculpatory statements made to the social worker. Driscoll relies on Killough v. United States (D. C. Cir. 1964), 336 Fed. 2d 929; State v. Rush (1929), 108 W. Va. 254, 150 S. E. 740; Commonwealth v. Edwards (1935), 318 Pa. 1, 178 Atl. 20; People v. Rockover (1947), 296 N. Y. 369, 73 N. E. 2d 555. But none of these cases use the term “estoppel” although they do involve the question of admissibility of statements given after promises of nondisclosure. As we read these cases, the questioner was in such an official capacity or authoritative position that the government should be bound by the promise of the official.4 The *706social worker in the instant case bore no such relationship to the government.

We are urged to create by case law a privileged confidential relationship for private and governmental social workers. This is possible and the four prerequisites for the granting of such testimonial privilege have been well stated in 8 Wigmore, Evidence, p. 527, sec. 2285. These are: (1) The communications must originate in a confidence they will not be disclosed; (2) confidentiality must be essential to the full and satisfactory maintenance of the relation between the parties; (3) the relationship should be one which, in the opinion of the community, ought to be sedulously fostered; (4) the injury which would inure to the relationship by disclosure must be greater than the benefit thereby gained for the correct disposal of litigation. Some authorities have discussed the application of these elements to social workers and to psychotherapists 5 and at least one urges that the creation of privileged communication in this new area should be left to the legislature.6 We think public policy is not so definitely compelling or clear or the area so limited that we should grant testimonial confidentiality by court decision to social workers.

Driscoll argues that because one who commits sexual intercourse with a child necessarily takes indecent liber*707ties with the privates of a minor and consents to the indecent use of his privates, the crimes of taking indecent liberties and indecent use is an included crime of sexual intercourse with a child. While intercourse may be taking indecent liberties, some indecent liberties are not intercourse. Although one may be charged with a crime and an included crime, he may only be convicted of one and not both. See. 939.66, Stats.7 The acts of fellatio and cunnilingus are not intercourse and it is clear they took place prior to the intercourse. Although acts of sex perversion and intercourse may be proximate in time, the acts are distinct and the continuity in time does not blend the former acts into the latter. Consequently, the acts of fellatio and cunnilingus with a child are not included crimes of sexual intercourse with a child, although all three may constitute indecent liberty or use.

We. find no merit in the argument the information was multiplicitous. The facts do not present a series of similar acts which are in reality a continuous course of conduct. But even if we adopted the singular-act view, separate charges may be based upon a single act if it involves violation of several provisions of the statutes. See sec. 939.65, Stats.;8 State v. Chacon (1971), 50 Wis. 2d 73, 183 N. W. 2d 84.

Before trial Driscoll moved to prevent the state from cross-examining him as to past convictions. He had been convicted in 1951, some eighteen years prior to the *708present trial, of contributing to the delinquency of a minor. The court reserved its decision until it reached the end of the state’s case, at which time it ruled against Driscoll on the ground that he could prevent any harm from the admission of a single conviction.

On cross-examination the state under authority of sec. 885.19, Stats.,9 asked Driscoll if he had been previously convicted of a crime. Driscoll admitted he had. By so doing the state was prevented from putting into evidence the nature of the crime; but likewise, because of the nature of the crime, Driscoll could not, without damage to himself on the issue of guilt, explain that the conviction had no relevancy to his truthfulness or veracity. In admitting the evidence, the trial court relied on Rule 303 of the American Law Institute Model Code of Evidence adopted in Whitty v. State (1967), 34 Wis. 2d 278, 294, 149 N. W. 2d 557. While WMtty did not involve the admissibility of a conviction for impeachment purposes, nevertheless the rationale of Whitty of balancing the relevancy of the evidence against prejudice on the guilt issue is applicable.

Rule 303 of the Model Code is not restricted to certain types of evidence but applies to any evidence when the judge in his discretion finds its probative value is outweighed by the risk its admission will have on the fairness of the trial. Here, the admission of a crime which occurred eighteen years before without revealing its nature would have very little prejudicial effect on the issue of guilt. While remoteness alone is not the determining factor of admissibility, it is an element to be taken into consideration. Although sec. 885.19, Stats., *709allows evidence of conviction for impeachment purposes, it is not confined to crimes which relate to honesty or veracity. Rausch v. Buisse (1966), 33 Wis. 2d 154, 168, 146 N. W. 2d 801; Nicholas v. State (1971), 49 Wis. 2d 683, 692, 183 N. W. 2d 11. Consequently, the admissibility under this section is subject to constitutional guarantees requiring a fair trial and due process. All the cases cited by Driscoll on remoteness 10 agree the question of admissibility is one which lies within the sound discretion of the trial court. We think the guidelines adopted in Whitty govern the exercise of that discretion and recognize the constitutional problems involved. While another trial court could well have differed in the exercise of its discretion on these facts, we are not prepared to hold there was an abuse of discretion allowing the evidence of this conviction in the record.

By the Court. — Judgment and order affirmed.

(concurring). This writer agrees with the majority that this court ought not grant testimonial confidentiality to social workers. However, the refusal so to do ought to be based on the ground that the setting of the public policy in this area and in this regard is a part of the legislative function, not the judicial function, under our tripartite form of government. It is for the legislature, not the courts, to determine whether communications between social workers and those they serve or counsel are to be privileged.