dissenting.
I dissent and would reverse the Commonwealth Court’s affirmance of the Pennsylvania Labor Relation Board’s ruling of law that caseload of the bargaining unit employees is a matter of “inherent managerial policy” and that worker caseload is not a subject of mandatory collective bargaining under Section 701 of the Public Employe Relations Act, (PERA) 43 P.S. § 1101.701.
In reaching its decision, the majority exhibits a degree of deference to the Board’s determination of a matter of law that is not justified by statute or precedent. This exaggerated deference stems from the jumbling together of the appropriate standard of appellate review of Board findings of fact with the standard of review of the Board’s conclusions of law. The majority incorrectly states “the issue here is whether there was substantial evidence on the record to support the Board’s conclusion that assignment of caseload was a managerial prerogative, and/or whether the Board erred as a matter of law in making its conclusion.” Majority op. at 241 (emphasis added). The majority then goes on to
hold merely that there was substantial evidence on the record as a whole to support the Board’s conclusion that discretion over the assignment of caseload in the *246Commonwealth’s social service system had a vital impact on the policy of the system so to outweigh the employee’s interest in the issue, as affecting wages, hours and terms and conditions of employment----
At 244-45 (emphasis added).1
This is obviously a misstatement of the appropriate standard of appellate review of the Board’s rulings of law. The correct statement of this standard is “whether the findings of the Board are supported by ‘substantial evidence’, and ‘whether the conclusions drawn from those facts are reasonable and not capricious, arbitrary, or illegal.’ ” St. Joseph’s Hospital v. Pennsylvania Labor Relations Board (PLRB), 473 Pa. 101, 104, 373 A.2d 1069, 1071 (1977) (citations omitted). While the majority initially recognizes this correct standard of appellate review, at 241, the subsequent language utilized indicates clearly that the majority has reviewed the conclusions of law as if they were findings of fact and, finding substantial evidence to support the conclusions, has deferred to the Board’s “expertise”.
There is certainly a need to defer to the Board’s expertise regarding its factual determinations, and, accordingly, we are bound by the Board’s fact findings and reasonable factual inferences where substantial, credible evidence supports such findings and inferences. See St. Joseph’s Hospital v. PLRB, supra and PLRB v. Mars Area School District, 480 Pa. 295, 389 A.2d 1073 (1978). However, it is neither desirable, wise nor permissible to so restrict our review of Board determinations of matters of law and this Court would abdicate its responsibility to interpret the laws of this Commonwealth were we to affirm an agency’s conclusion of law merely because there was “substantial evidence” to support it. The deference given to an agency’s factual determination is totally out of place in the context of appellate review of conclusions of law. Where an error has been committed by the Board in its application of the law to the facts which it has found (and which are supported by substantial evidence), then the conclusions erroneously *247drawn by the Board are not “reasonable”, and perhaps, in a given case, are “capricious, arbitrary or illegal.” Where such an error of law has occurred, an appellate court is obligated to correct that error by reversing or modifying the Board’s order.
There is no doubt that the determination of whether an item is a mandatory subject of collective bargaining under Section 701 or a “meet and discuss” item under Section 702 is a question of law. In PLRB v. State College Area School District, 461 Pa. 494, 507, 337 A.2d 262 (1975), this Court stated:
[W]e hold that where an item of dispute is a matter of fundamental concern to the employes’ interest in wages, hours and other terms and conditions of employment, it is not removed as a matter subject to good faith bargaining under section 701 simply because it may touch upon basic policy. It is the duty of the Board in the first instance and the courts thereafter to determine whether the impact of the issue on the interest of the employe in wages, hours and terms and conditions of employment outweighs its probable effect on the basic policy of the system as a whole, (emphasis added).
While this balancing test does not purport to establish bright lines, it is apparent that the more directly an item affects an individual employee’s “wages, hours and other terms and conditions of employment,” the more likely that item will be determined to be a legitimate subject of mandatory collective bargaining.2 In my opinion, it is difficult to conceive of a subject matter more directly related to “hours” of employment than employee caseload or workload. As appellants state in their brief at 8, n. 2:
As used in the context of these proceedings, the concept of “workload” includes both the number of cases *248assigned to each worker and the type and degree of difficulty of those cases. While the terms “workload” and “caseload” have sometimes been used interchangeably, it is important to note that the Union’s concern here is not with the absolute number of discrete cases assigned a given employee, but rather with the quantum of work required by a particular configuration of case assignments. The Union does not seek to control the overall workload administered by the Department of Public Welfare or the determination of what constitutes the work of the Department.
In PLRB v. Mars Area School District, supra, this Court recognized that matters affecting the employee’s “quantum of work” are subjects of mandatory collective bargaining under section 701. That case held that the employer school district’s unilateral termination of teacher-aides and substitution of volunteer workers was a violation of the district’s duty to bargain in good faith over a subject of mandatory collective bargaining. In reaching this conclusion of law, Mr. Justice (now Chief Justice) Roberts, speaking for the Court, stated:
The Board properly concluded that the [district’s unilateral] decision’s immediate impact on wages, hours, terms, and conditions of employment far outweighs any considerations of managerial policy. Appellee [school district] was therefore required to bargain under Section 701.
In Dublin Professional Firefighters v. Community Services Dist., 45 Cal.App.3d 116, 119 Cal.Rptr. 182 (1st Dist.1975), the court, interpreting a similar statute, held that a public agency was obliged to bargain in good faith over assignment of overtime work to temporary employees-rather than regular employees previously performing the same work. “The assignment of overtime work to temporary service personnel will have an obvious effect on the workload and compensation of the regular employees .... ” (emphasis added).
Similarly in the instant case, the “quantum of work” performed by an employee, i.e. the caseload or workload, *249has an obvious effect on the employee’s hours and rate of compensation. In its initial determination of August 6, 1979 upon remand from this Court, the Board adamantly espoused this conclusion of law (i.e., that caseload directly affected wages, hours and other terms or conditions of employment, and hence was bargainable under Section 701), stating:
Given that no two states are precisely alike in their systems of collective bargaining and scope of collective bargaining, there is nonetheless a strong consensus that workload is mandatorily negotiable. Los Angeles Court Emp. Assn. v. County of Los Angeles, 33 Cal.App.3d 1, 108 Cal.Rptr. 625 (1973) (social workers; caseload); West Hartford Edu. Assn. v. DeCourcey, 162 Conn. 566, 295 A.2d 526 (1972) (teacher workload); Onodaga Community College Federation of Teachers, 11 N.Y.Perb.Para 3045 (1978) (college professors’ workload); Annotation, “Bargainable or Negotiable Issues in State Public Employment Labor Relations”, 84 A.L.R.3d 242 (1978); Sackman, “Redefining the Scope of Bargaining in Public Employment”, 17 Boston College Law Review, 155 (1977).
These judicial and administrative decisions recognize that unions exist, in a large part, to bargain about how much work their members are supposed to do. Bargaining about mandatory subjects such as wages and hours would be meaningless if the employer could simply increase the amount of work to be done during a given period of time.
Application of the State College balancing test to the facts of the present case leads this Board to conclude that workload is a mandatory subject of bargaining____
Although workload restrictions will affect, to some degree, the policy-making functions of the Commonwealth, the Supreme Court has ruled in State College that this alone will not render a particular subject non-mandatory under Section 702. The potential impacts the *250Commonwealth has cited could also result from higher wages, shorter hours or changes in other admittedly mandatory subjects of collective bargaining. The Commonwealth has substantial freedom to determine what functions social workers will perform and what public services it will offer. Qualitative performance standards may be established and enforced through appropriate disciplinary procedures. Workload standards will have no impact on selection and direction of personnel or organizational structure. The overall budget, i.e. the establishment of the budget itself, will not be affected any more than a wage increase would affect it. Utilization of technology would not be prohibited although there might be some inhibitions on its introduction if too rigid a workload standard were adopted.
The balance in this case is tipped rather strongly in favor of mandatory negotiability. The potential impacts of workload on the employes sharply outweigh those on the Commonwealth. The Commonwealth’s argument assumes that mandatory negotiation is equivalent to agreement. There is no obligation under Act 195 to agree. The Commonwealth need not agree to any workload restrictions it does not like. If a proposal is agreed to and it has, in practice, unduly adverse effects, then the parties can readjust the workload standards in subsequent negotiations. Collective bargaining is an ongoing process of adjustment and readjustment.
From Decision and Order of Board dated August 6, 1979 at 6-7, reproduced record at 289a-290a. (emphasis added).3
The majority’s analysis and result resurrects a point of view that had been taken by the majority of the Commonwealth Court in PLRB v. State College Area School District, 9 Pa.Cmwlth. 229, 306 A.2d 404 (1973) which had been thoroughly rejected by this Court on appeal. The concern *251expressed by Judge Kramer in his cogent dissenting opinion in that case is equally applicable today:
[Fjollowing the reasoning of the majority, I believe it would be relatively easy for me to argue that almost everything touching upon teachers’ employment could be argued to be a matter of “inherent managerial policy”. If that is the result of the tack taken by the majority in analyzing what is meant by “inherent managerial policy”, then I believe the legislative intent of Act 195 will have been thwarted.
Quoted with approval in the majority opinion on appeal, 461 Pa. 494, 504 n. 7, 337 A.2d 262, 267 n. 7.
For the foregoing reasons, I would hold, as a matter of law, that the Board erred in its determination that employee caseload is not a proper subject of mandatory collective bargaining under Section 701, and I would reinstate the Board’s Nisi Decision and Order of August 6, 1979.
. The majority also states that the Board's “conclusion is amply supported by evidence in the record.” At 243.
. "The key, as we see it, is how direct the impact of an issue is on the well-being of the individual teacher, as opposed to its effect on the operation of the school system as a whole.” National Education Ass’n of Shawnee Mission, Inc. v. Board of Education of Shawnee Mission Unified School District No. 512, 212 Kan. 741, 753, 512 P.2d 426, 435 (1973), quoted with approval in PLRB v. State College Area School District, supra at 461 Pa. 506, 337 A.2d 262.
. On February 5, 1981, the Board reversed itself, with Board member Joseph J. Licastro dissenting, and reached the conclusion that caseload was not a subject of mandatory collective bargaining under section 701. The reasons offered for this change of heart are not persuasive, especially in light of the adamance of its prior opposite *251conclusion and since no additional evidence had been taken. While I agree with the majority that the Board has the ability to reverse itself, see section 1501, 43 P.S. § 1101.1501, nevertheless the Board’s retreat from its strong position of August 6, 1979 seriously undermines the value of the Board’s “expertise” on this issue and further demonstrates the impropriety of granting any deference to the Board’s determination of conclusions of law.