dissenting:
I dissent because, in my opinion, (1) the Public Service Commission does not, and constitutionally cannot, exercise any judicial or so-called “quasi-judicial” powers or functions so that Rule III-A purports to relate to a non-existent function and is void on its face; (2) assuming, arguendo, that the Commission can or does exercise any “quasi-judicial” function, it has been granted no power by the General Assembly to promulgate Rule IIT-A; and (3) Rule III-A is too vague and indefinite on its face to be a valid rule.
0)
As our predecessors stated in Public Service Comm’n v. Philadelphia B.&W.RR. Co., 155 Md. 104, 114, 141 A. 509, 514 (1928):
*586“The Public Service Commission of Maryland was created by chapter 180 of the Acts of 1910. It exercises a naked statutory authority, and has no powers save such as were expressly granted to it by the legislature, and such implied powers as are necessary to enable it to exert its express powers.” (Emphasis supplied)
As Judge (later Chief Judge) Henderson aptly stated in Commissioners of Cambridge v. Eastern Shore Public Service Co., 192 Md. 333, 339, 64 A. 2d 151, 154 (1949):
“The Public Service Commission is essentially a regulatory body.”
In the Commissioners of Cambridge case it was pointed out that the validity or extent of charter power or franchises of a public service company was a judicial question and that the Commission had no power or authority to pass upon such questions. Indeed, the General Assembly would have no power to confer judicial powers upon the Commission in view of the mandatory provisions of Article 8 of the Declaration of Rights of the Maryland Constitution, providing for the separation of governmental powers and which provides:
“That the Legislative, Executive, and Judicial powers of Government ought to be forever separate and distinct from each other; and no person exercising the functions of one of said Departments shall assume or discharge the duties of any other.” (Emphasis supplied)
This mandatory language necessarily, in my opinion, prevents: the General Assembly, as the legislative branch of the State Government, from constitutionally delegating to any administrative body created by it any judicial power or so-called quasi-judicial power. Our predecessors have so held. As Chief Judge Sloan, for a unanimous Court, stated in Dal Maso v. Board of County Comm’rs of Prince George’s County, 182 Md. 200, 205, 34 A. 2d 464, 466 (1943):
“The petitioners contend that the order of the defendant amending the zoning regulations is res judi*587cata, which means, of course, that it has the permanence of a judgment or decree of a court of competent jurisdiction. There is some confusion as to the nature and character of these administrative boards, and there are many opinions and text writers who refer to them as quasi-judicial. They do hear facts and, based on them, make decisions, but those decisions are not judgments or decrees. If their findings, resolutions, or orders are resisted or ignored, they must call on the courts to enforce them. Administrative boards and officials are arms and instrumentalities of the Legislature, and are not judicial at all; they belong to and derive all their authority from the legislative branch under our form of government. In this State, all judicial authority is only such as is provided for by Article 4 of the Maryland Constitution, and it has been decided that only judicial functions can be exercised which find their authority in that Article (Day v. Sheriff, 162 Md. 221, 159 A. 602; Humphreys v. Walls, 169 Md. 292, 181 A. 735; Quenstedt v. Wilson, 173 Md. 11, 194 A. 354; Levin v. Hewes, 118 Md. 624, 86 A. 233), and that no court not coming within its provisions can be established in this State. This forbids any power in the Legislature to clothe administrative boards with any judicial authority. There may be states in which it can be done, but Maryland is not one of them.”
Notwithstanding this clear holding, this Court, without overruling Dal Maso, has from time to time indicated that various administrative boards do exercise so-called quasi-judicial functions which in some way bring with them the incidents of judicial proceedings such as res judicata, and also the right to cross-examine as a constitutional right. I have protested, without avail, against what I consider to be erroneous decisions in this regard. As I stated in my dissenting opinion in State Insurance Comm’r v. National Bureau of Casualty Underwriters, 248 Md. 292, 315, 236 A. 2d 282, 295 (1967):
“I have been critical of what I consider a departure from the doctrine of separation of powers by this Court *588in a number of prior cases. See my dissenting opinions in MacDonald v. Board of County Comm’rs of Prince George’s County, 238 Md. 549, 557 to 608, especially pages 602-608, 210 A. 2d 325, 329-358, especially pages 354-358 (1965); Woodlawn Area Citizens Ass’n v. Board of County Comm’rs of Prince George’s County, 241 Md. 187, 201-218, especially pages 203-213, 216 A. 2d 149, 158-168, especially pages 159-165 (1966) and most recently in Delbrook Homes, Inc. v. Mayers, 248 Md. 80, 234 A. 2d 880 (1967); and my concurring opinions in Hyson v. Montgomery County Council, 242 Md. 55, 77-84, 217 A. 2d 578, 592-595 (1966); and Gaywood Community Ass’n v. Metropolitan Transit Authority, 246 Md. 93, 101-105, 227 A. 2d 735, 739-742 (1967).”
In my dissenting opinion in Woodlawn Area Citizens Ass’n, Inc. v. Board of County Comm’rs for Prince George’s County, 241 Md. 187, 208-09, 216 A. 2d 149, 162 (1966), I stated:
“In Schultze v. Montgomery County Planning Board, 230 Md. 76, 79, 185 A. 2d 502 (1962) and in Kay Construction Co. v. County Council for Montgomery County, 227 Md. 479, 486, 177 A. 2d 694 (1962), both cited in the majority opinion, there is dicta which indicates that the County Council in Montgomery County does exercise ‘quasi-judicial functions.’ In my opinion this is unfortunate language, unnecessary to the decisions in those cases, which gives rise to the notion that the holding in Dal Maso has been somewhat impaired but not overruled. As I see it, in both cases the County Council was exercising a ‘restricted legislative function,’ not a 'quasi-judicial function.’ It has been my observation that when the prefix ‘quasi’ is appended to a well-defined word, distinctions are blurred, fuzzy thinking is invited and error often results. Its use should be avoided. If the restrictions placed upon the exercise of legislative power are those usually associated with the exercise of judicial functions, one may inquire if the characterization of *589the function as ‘quasi-judicial’ really does any harm and if the suggested difference in characterization is not merely a semantic exercise? 1 think not. These are quite different concepts and result in different applications of the requirements of due process of law, depending upon whether a function is ‘legislative,’ on the one hand, or ‘judicial’ on the other, ff the function is legislative, due process of law does not require a hearing, the opportunity for counsel, the taking of testimony (under oath or otherwise), the right of confrontation or cross-examination and other time-honored safeguards associated with the exercise of a judicial function. The only limitations upon the exercise of the legislative power are those specifically set forth in the Constitution, as for example, the prohibition against the taking of private property other than for public use and upon the payment of just compensation, and that the legislation be not unreasonable, arbitrary and capricious and thus a denial of due process of law. When the legislative power is delegated by the General Assembly to a local legislative body the grant is unlimited, except as limited by the statute making the grant of legislative power, subject, of course, to the constitutional limitations mentioned. In short, the power of review of a court, either upon an original proceeding or upon appeal, is limited to the constitutional limitations mentioned and such limitations as the statute imposes.”
In short, in my opinion, the Commission has not been, and could not be, delegated any judicial or quasi-judicial powers by the General Assembly. All of its powers are legislative and regulatory in nature as many of our prior cases have indicated. Rule III-A purports to regulate a non-existent function of the Commission and is void on its face.
(2)
If it be assumed for the argument that the Commission can or has “quasi-judicial” powers and functions, it nevertheless has not been granted power by the General Assembly to pro*590mulgate Rule III-A.1 No one contends that any provision of Code (1957), Article 78—The Public Service Commission Law —specifically grants such a power to the Commission. Can the grant of such a power reasonably be inferred from the provisions of Article 78 mentioned in the majority opinion? In my opinion it cannot be inferred; on the contrary, the implications are that no such power was intended to be granted by the General Assembly.
For example, the General Assembly conferred certain rights upon "any party to any hearing” by § 82 of Article 78, including the right to summon witnesses, present evidence, present arguments, cross-examine and submit rebuttal evidence. All of these rights are usually associated with judicial proceedings but by § 82, they are granted by the General Assembly for all proceedings before the Commission. No distinction is made between types of proceedings (doubtless because it was thought that all proceedings were legislative in nature) and there is no suggestion that any of these rights must be exercised by members of the bar on behalf of “any party to any hearing.” If the General Assembly had thought that this policy was desirable in any proceeding it would either have so provided expressly or have granted the Commission authority to adopt such a policy by rule, setting up appropriate guides and standards. The absence of any such provision at this likely place in the statutory plan, indicates to me that the General Assembly had no notion of either establishing such a policy itself or of delegating authority to the Commission to adopt such a policy by rule.
Then too, § 76 of Article 78 which provides, in part, that “The Commission should not be bound by the technical rides of evidence or procedure of courts of law or equity” (emphasis supplied), indicates to me that the General Assembly did not *591intend that any proceedings before the Commission should necessarily he conducted by members of the bar who generally conduct proceedings before courts of law or equity. Here again is a likely place for the General Assembly to make provision for limiting the conducting of part of the proceedings by attorneys-at-law and the absence of such a limitation or grant of power to the Commission to compel such a limitation by rule, indicates to me the absence of any legislative intent that the Commission have such power. In my opinion, the statute is clear in this regard.
This is emphasized by the conceded fact that for approximately 60 years—indeed since the original passage of the Public Service Commission Law in 1910—parties have been represented by persons not members of the bar in all proceedings before the Commission. There was no idea, apparently, that such representation in any proceeding before the Commission was unlawful or constituted the unlawful practice of law. The Commission permitted such representation in all cases, doubtless because it was of the opinion that such representation in all proceedings was valid, lawful and conferred upon the parties as a matter of right under the Public Service Commission Law. If the statute be thought to be ambiguous in this regard, this contemporaneous construction of the law continuing for approximately 60 years without exception, should be most persuasive to us that this type of representation in all proceedings for all parties was lawful. As Judge Melvin, for the Court, stated in Wells v. Price, 183 Md. 443, 457, 37 A. 2d 888, 895 (1944):
“* * * this Court has already declared in clear language that the long uninterrupted and unvarying construction put upon a statute by administrative officials is entitled to great weight in law, and that courts should refrain from putting a different interpretation upon the statute except for the most potent and urgent reasons. Arnreich v. State, 150 Md. 91, 101, 132 A. 430; American-Stewart Distillery Co. v. Stewart Distilling Co., 168 Md. 212, 177 A. 473.”
The majority indicates that this well established doctrine of statutory construction is not applicable because “the questions *592here-posed were never raised until brought up in 1966; so that there could not reasonably arise a presumption of legislative acquiescence in an administrative determination of an ambiguous legislative provision.”
The cases indicate to me, however, that the continuous or practical construction of a statute as a rule for the interpretation of ambiguous statutes does not begin its operation with a challenge to the administrative practice under the statute; rather it begins with the first or contemporaneous administrative practice under the statute and for this reason is a valuable guide for the courts in construing the statute as this gives an authoritative construction of the statute ante litem motam. When the contemporaneous construction by the administrative agency is long continued, without interruption, the courts will not disregard it except “upon the most imperious grounds.”. Graham v. Joyce, 151 Md. 298, 306, 134 A. 332, 335 (1926).
It cannot be assumed by us that the General Assembly' was not familiar with so formidable an administrative construction continued without interruption for so many years; the presumption is to the contrary. See Dvorine v. Castelberg Jewelry Corp., 170 Md. 661, 674, 185 A. 562, 568 (1936).
The long and unvarying construction by the administrative agency of the legislative language “gives the sense of the community” in regard to the terms used by the legislative branch of the State government. Judge Offutt, for the Court, stated the rule as follows in Leitch v. Gaither, 151 Md. 167, 176-77, 134 A. 317, 320 (1926):
“It is said in Lewis’ Sutherland on. Statutory Construction, par. 472: ‘The aid of contemporaneous construction, is invoked where, the language of a statute is of doubtful import and cannot be made plain by the help of any. other part of the same statute, nor by the assistance of any act in pari materia which may be read with it, nor of the course of the. common law up to the time of its enactment. Under' such circumstances the court may consider what was the construction put upon the. act when it first came into operation. Where this has been given by enactment it is conclusive. A *593contemporaneous construction is that which it received soon after its enactment. This, after the lapse of time, without change of that construction by legislation or judicial decision, has been declared to be generally the best construction. It gives the sense of the community as to the terms made use of by the legislature. If there is ambiguity in the language, the understanding of the application of it when the statute first goes into operation, sanctioned by long acquiescence on the part of the Legislature and judicial tribunals, is the strongest evidence that it has been rightly explained in practice. A construction under such circumstances becomes established law/ And this court in a recent case has announced the same rule. Burroughs Adding Machine Co. v. State, 146 Md. 192.”
It should also be kept in mind in this connection that by § 60 of Article 78 of the Commission, itself, “may recommend or prepare legislation as to any matter within or related to its jurisdiction.” It is significant, I think, that for approximately 60 years the Commission did not find it necessary or in the public interest to request the General Assembly to enact the substance of Rule ITI-A or to grant the Commission the power to adopt it by rule, with appropriate guides and standards. Then too, it should be kept in mind that there was a general revision, with a repeal of the old Public Service Commission Law and the enactment of a new statute, by Chapter 441 of the Acts of 1955. Even in this general revision, no such power was granted.
In addition to the contemporaneous and uninterrupted practice for some 60 years by the Commission, itself, the Attorney General of ’Maryland in his opinion to the State Industrial Accident Commission (23 Op. Atty. Gen. 427) in 1938 in regard to the rule-making power of the State Industrial Accident Commission on the subject matter involved in Rule III-A, stated:
“We find nothing in the statute to indicate a legislative intent to allow the Commission, which need not be composed of lawyers, to limit appearance before it.”
*594The Workmen’s Compensation Law at the time of the opinion gives rule-making powers as broad or perhaps even broader than those granted to the Public Service Commission. It is correct, as the majority opinion points out, that the Attorney General in the opinion mentioned, reached no conclusion in regard to the power of the State Industrial Accident Commission to adopt a rule similar to Rule III-A as it advised the bringing of a test case, but the opinion did state that the Attorney General found nothing in the Workmen’s Compensation Law to indicate a legislative intent that it had such a power.
The principal thrust of the majority’s opinion sustaining the power of the Commission to adopt Rule III-A is that the appearance of laymen, representing parties, and their participation in the conduct of proceedings of a “quasi-judicial” nature before the Commission is the unlawful practice of law and hence the Commission may by rule prevent this alleged unlawful practice of law by rule. I cannot agree with either of these statements.
In the first place, such an appearance and participation by a layman representing a party before the Commission is not, in my opinion, unlawful practice of law in Maryland, whatever may be the holdings of courts of other States. We decided in Bastian v. Watkins, 230 Md. 325, 187 A. 2d 304 (1963), that the admission of a resident of Maryland to practice law in this State is a legislative and not a judicial function. Judge Horney, for the Court, stated in Bastian:
“It has long been recognized that the admission of a resident of Maryland to practice law is a legislative, not a judicial, function in that the right may constitutionally be regulated by statute. See In re Maddox, 93 Md. 727, 50 Atl. 487 (1901). See also In Re Taylor, 48 Md. 28 (1877); State v. Johnston, 2 H. & McH. 160 (1786).” (230 Md. at 329, 187 A. 2d at 306)
The General Assembly by the Act of 1898, Chapter 139 gave exclusive power to this Court to admit applicants to practice law and this Court has exercised this power since that time. The General Assembly, however, has never delegated to us the *595power to determine what constitutes the unlawful practice of law, but has exercised this power itself, beginning with Chapter 48 of the Acts of 1715.
Article 10, § 1 of the Maryland Code (1968 Repl. Vol.) provides as follows:
“No person shall practice the profession or perform the services of an attorney at law within this State without being admitted to the bar as hereinafter directed; and any person who shall give legal advice, represent any person in the trial of the case at law or in equity including the trial of any case before any trial magistrate or judge of any people’s court or any proceedings conducted in orphans’ courts of the State, or in cases before the People’s Court of Baltimore City where the amount involved exceeds the sum of $100.00 except cases arising under §§ 455 to 462, inclusive, of the Charter and Public Local Laws of Baltimore City (1949 Edition) or prepare any written instrument affecting the title to real estate, or give advice in the administration of probate of estates of decedents in any of the orphans’ courts of this State, for pay or reward shatt he deemed an attorney at law for purposes of this article.” (Emphasis supplied)
Section 32 of Article 10 implements the provisions of § 1 and provides:
“Any person who shall exact, demand, take or receive from any person whatsoever any fee, gratuity, gift or reward for his advice or service as an attorney at law without having been admitted to the bar agreeably to the provisions of this article shall be guilty of a misdemeanor, and upon conviction thereof shall be liable to a fine of not more than one hundred dollars, or confinement in jail for not more than thirty days, or both fine and imprisonment, in the discretion of the court.” (Emphasis supplied)
By the Act of 1961, Chapter 217, the General Assembly adopted an “ALTERNATIVE REMEDY FOR THE UNAUTHORIZED PRACTICE OF LAW.” This was the Model *596Act Providing- Remedies for the Unauthorized Practice of Raw and-provided that the Attorney General or any-organized bar association in Maryland “may maintain an action for-injunctive relief in the-circuit court of any county or in the-equity courts of the Supreme Bench of Baltimore City against any person who renders, offers to render, or holds himself out as rendering any service which constitutes the unauthorized practice of law” (Code (1957), Article 10, § 26A (1968 Repl. Vol.)). It was further provided in the Act of 1961 that the “remedies and procedures provided in this subtitle are in addition to and not in .substitution for other available remedies and procedures” (Code (1957), Article 10, § 26C (1968 Repl. Vol.)).
For both the purposes of criminal prosecution under § 32 or for injunctive relief under § 26A, the unlawful practice of law'is defindd in ‘ §. 1 of Article TO. In regard to representation of persons :in proceedings, the definition is limited to courts of law or equity, before any trial magistrate or judge of any people’s court or any, proceedings conducted in orphans’ courts of the State, or in cases -before the People’s Court of Baltimore City where the amount exceeds the sum of $100 except cases arising under §§ -455 .to 462. of the Baltimore City Charter (landlord and tenant cases in Baltimore City). Not only is there no mention whatever of the, representation of persons not members of the bar before administrative tribunals, but such representation is not the practice of law in landlord and tenant case's and cases involving leks'Than $100 ifi the People’s Court of Baltimore City. How then does an appearance of a person not á member of the bar fór a party before the'Commission constitute the unlawful' prhctice Of law under' the Maryland' státúté? Tt seems to hie that it clearly does not as the‘ inclusión of the courts before which, with certain exceptions, representation by laymeri,4sbMat'edTo)‘tíe' úhlaMúl practice of! law, necessarily excludes administrative bodies not mentioned in the' statute, in accordance with'the maxim inclúsio unius est exclusio alterius. See American Security and Trust Co. v. New Amsterdam Casualty. Co., 246 Md. 36, 41, 227 A. 2d 214, 215-17 (1967), in which we construed Code (1957), Article 39B, § 9 and in which Judge Horney,for the Court stated:
*597"Clearly the trust company insofar as the record, shows was not a purchaser for a fair consideration and only a purchaser is afforded the provisions of the statute. Had the legislature intended to include a mortgagee within the terms of the statute, it would undoubtedly have done so, and since it did not, the , implication is that mortgagees were purposely excluded.”
See also Gay Investment Co. v. Comi, 230 Md. 433, 438, 187 A. 2d 463, 466 (1963).
Our predecessors in Rehm v. Cumberland Coal Co., 169 Md. 365, 181 A. 724 (1935), held that the representation by a collection agency of a party before the presiding justice of the People’s Court of Baltimore City (as then constituted) in a case involving $18 was not practicing law under Article 10 of the Maryland Code. Judge Johnson, for the Court, stated:
‘‘Briefly stated, Rehm’s contention is that the conduct of the collection agency in the People’s Court of Baltimore City was violative of the spirit and intent of the above sections of the Code, the agency having no right to practice the profession of law; that the word ‘attorney’ as used in section 626 of the Baltimore City Charter, above quoted, necessarily means ‘attorney at law’ and, the agency not being such, the People’s Court of Baltimore City acquired no jurisdiction over the debtor, and the judgment rendered is null and void.
“We have been referred by appellant to a number of decisions in other states holding that the word ‘attorney,’ when used in a statute, means ‘attorney at law,’ and apparently taking the view that one who participates in the trial of causes before a j ustice of the peace is engaged in the practice of law, but such decisions are not persuasive in this case, when we consider that this word has been used by the Legislature in several statutes relating to procedure before justices of the peace in Baltimore City, beginning as early as 1821. It must be. presumed that in the use of the word the Legislature was fully cognizant of the fact that throughout this period it had not been accepted by the public as be*598ing synonymous with ‘attorney at law,’ and that by its continued use of the word in subsequent statutes for more than a century it acquiesced in that view.
“We are, therefore, of the opinion that the acts of the collection agency in this case did not amount to unlawful practice of law within the meaning of statutes referred to, that its conduct as agent of the coal company in the Baltimore City Court was legally permissible, and the People’s Court acquired jurisdiction over the parties.” (169 Md. at 367-68, 181 A. at 725)
Judge Johnson also pointed out that although a justice of the peace is a “judicial officer” under the provisions of the Maryland Constitution, his office is not associated with the idea of a “court.” In the present case, the Public Service Commission is likewise not associated with the idea of a “court” and is not mentioned in the Constitution of Maryland as a “judicial body.”
If representation of a party by a person not a member of the bar in a case before a justice of the peace—the presiding justice in the People’s Court of Baltimore City (as then constituted)—and declared to be a judicial office by the Maryland Constitution, is not the unlawful practice of law, a fortiori, such representation before the Commission is not the unlawful practice of law. The majority seeks to distinguish Rehm from the instant case because it is thought to be grounded “on two bases which are not here involved, the first explicit, the second implicit. First, the word ‘attorney’ in the Baltimore City statute had over a period of one hundred years acquired the gloss recognized by the legislature of attorney in fact as well as attorney at law the Court concluded. Second, the act performed by the corporate attorney in fact was so simple and so generally known and understood as not to require for its exercise legal skill, knowledge or training, and the amounts which could be involved under the then jurisdictional limits of the People’s Court were so small that the cost to a litigant of retaining a lawyer would not ordinarily have been warranted.” In my opinion, this distinction is not persuasive. The opinion in Rehm indicates that the appellant also relied upon the sections of Article 10 *599punishing the unlawful practice of law and I find nothing in the opinion that indicates the alleged “implicit” base for the opinion. What judge Johnson stated was:
“Although under the Constitution of the State a justice of the peace is a judicial officer, his office is entirely disassociated from the idea of a ‘court,’ in the common acceptation of that term. There is no special pleading before the justice (Code, art. 52, sec. 32), and the parties litigant, in person or by agents, have a right to participate in the proceedings. Md. Const. art. 4, sec. 1; Thomas’ Procedure in Justice Cases, sec. 2B, Authority of Attorney-at-Law; 16 R. C. L., p. 330; Weikel v. Cate, 58 Md. 105; Kane v. State, 70 Md. 546, 550, 17 A. 557; Benton v. Stokes, 109 Md. 117, 71 A. 532; Levin v. Hewes, 118 Md. 624, 86 A. 233.” (169 Md. at 368, 181 A. at 725)
In regard to the acquisition of the word “attorney” of a “gloss” over the period of 100 years, it might well be said that the contemporaneous and uninterrupted practice before the Public Service Commission for some 60 years had also given the Public Service Commission Law a “gloss” which this Court should recognize. In my opinion, the majority has not successfully distinguished Rehm, which, as 1 have indicated, I think is controlling in the present case.
Nor do I think that, assuming for the argument only, that the representation of a layman of a party before the Commission in “quasi-judicial” proceedings in the unlawful practice of law, the Commission is for that reason justified in promulgating Rule JII-A. Most certainly there is nothing in the Public Service Commission Raw which remotely suggests that one of the duties of the Commission is to suppress the unlawful practice of law. This suppression is accomplished by the Courts pursuant to the Acts of Assembly already mentioned, by a criminal’ court in which the accused would have a right to a trial by jury or by an equity suit in an equity court for an injunction under the alternative provisions of §§ 26A to 26E of Article 10. The General Assembly has not conferred upon the Commission the right to determine what constitutes the unlawful practice of law *600and to provide a third alternative method of suppressing it. No 'doubt if the Cfeneral Assembly had so intended,.-it would have added an appropriate section to the Act of 1961, Chapter 217 providing remedies for the unauthorized practice of law.
It is difficult for me to perceive how there can be any “analogy” of the rule-making power of the Commission to that of those rule-making administrative bodies under the Administrative Procedure Act, Maryland Code, Article 41, §§244-256, in view of the express provisions of §244 of Article" 41 that the Public Service Commission is excepted from the definition of agencies to which the Act applies.
(3)
In my opinion, the language of Rule III-A is -too vague and indefinite on its face to be a valid rule. Rule III-A requires that all parties, except individuals appearing in their own behalf, shall be represented by attorneys-at-law “when the Commission is performing a quasi-judicial function as distinguished from a legislative, executive or a ministerial function.” There is, however, no definition of what the “quasi-judicial function” is. As I am not able to know what it is, I believe that parties before the Commission may have the same difficulty. To illustrate the difficulty presented to a party in understanding the scope and application of this vague, undefined term, I refer to the description by the Chairman of the Commission, now Judge Liss, of what, in his opinion, a “quasi-judicial” question was as set forth in the majority opinion:
“The thing that gives us difficulty, and I suppose it’s really the crux of this case, is what is. to happen when you have a quasi-judicial question to consider, when there are exhibits to be prepared and filed, when there is examination and cross-examination of witnesses to be prepared, and when a record is being made which may ultimately reach the Court of Appeals, and is there not then a requirement that at least, as to that stage of the proceeding, that whoever comes in to be heard before the Commission ought to be represented by counsel.”
All of the described activities are present in a rate case, but *601our predecessors have held several times that the determination of rates is the exercise by the Commission of a legislative function. Bosley v. Dorsey, 191 Md. 229, 238, 60 A. 2d 691, 695 (1948); Public Service Commission v. United Railways & Elec. Co., 155 Md. 572, 580, 142 A. 870, 873 (1928); Public Service Commission v. Northern Central Ry. Co., 122 Md. 355, 388, 90 A. 105, 118 (1914). Who then can tell from the rule when a “quasi-judicial” function is involved when there is no definition or criteria in the rule and the only statement in the record by the Chairman of the Commission relating to the quasi-judicial function applies equally to a recognized legislative function? In my opinion, the provisions of Rule III-A are not sufficiently clear and definite to be a valid exercise of the rule-making power by the Commission if the Commission had such power, and thus was unreasonable, and arbitrary in the legal sense, resulting in a denial of due process of law forbidden by Article 23 of the Declaration of Rights of the Maryland Constitution. See Blum v. Engelman, 190 Md. 109, 57 A. 2d 421 (1948), in which Judge Delaplaine, for the Court, stated:
“It is well settled that a statute which prohibits the doing of an act in terms so vague that persons of ordinary intelligence must necessarily guess at its meaning and differ as to its application violates the constitutional guarantee of due process of law.” (190 Md. at 113, 57 A. 2d at 422)
The same doctrine applies to rules promulgated by administrative bodies. See Northwest Steel Rolling Mills, Inc. v. Kendall, 210 F. 2d 283 (U.S. Emergency Ct. of Appeals 1954), cert. denied, 347 U. S. 960, 74 S. Ct. 709, 98 L. Ed. 1104 (1954); United States v. Pope, 189 F. Supp. 12, 21 (S.D.N.Y. 1960); In re Peppers, 189 Cal. 682, 688, 209 P. 896, 898 (1922). See also Comptroller v. Rockhill, Inc., 205 Md. 226, 233, 107 A. 2d 93, 97 (1954); 73 C.J.S. Public Administrative Bodies and Procedure,” §100 at 418-19 (1951).
Judge Cullen, in my opinion, was correct in passing the order of July 2, 1968 in which Rule III-A was annulled, set aside and made void as beyond the power of the Commission. For that reason, as well as for the other reasons stated above, I would affirm that order.
. The General Assembly might by statute require that parties must represent themselves or be represented by members of the bar, and not by compensated laymen in certain types of proceedings before the Commission even though such proceedings are legislative in character, or even perhaps delegate the power to make such a rule, with appropriate guides and standards to the Commission, but in the instant case it has neither acted itself nor delegated such a power to the Commission.