This case requires us to decide whether a decision rendered by the National Labor Relations Board (NLRB or Board) after a *104 remand from a decision of this court is consistent with that decision. Goodless Electric Company (Goodless) was first accused of unfair labor practices in 1994 when it refused to recognize a union for collective bargaining purposes. An administrative law judge exonerated Goodless, but the Board reversed his decision. We rеversed the Board, ruled that the Board’s precedents required a finding in favor of Goodless, and remanded the case to the Board for proceedings consistent with that decision. Misinterpreting that decision and its mandate, the NLRB once again decided on remand that Goodless had violated the law. We again reverse.
I.
Before beginning the discussion, we must establish a shorthand notation for three of the four decisions that have previously addressed this ease. An administrative law judge decided in favor of Goodless Electric Company, concluding that it had not engaged in unfair labor practices. The NLRB reversed this decision in
Goodless I. Goodless Elec. Co., Inc.,
A. Legal Background
A union must usually demonstrate majority support among an employer’s employees in order to enter a collective bargaining agreement with an employer. However, in the construction industry, the short-term nature of the employment and the contractor’s need for predictable costs and a steady supply of skilled labor makes such arrangements impractical. Thus, “[cjollective bargaining agreements in the construction industry are commonly negotiated before the employees are hired because employers must be able to fix labor costs to make bids, and have a supply of skilled craftsmen ready for quick referral.” Timothy Volk, Prehire Agreements in the Construction Industry, 9 J.L. & Com. 243, 245 (1989). In response to this industry practice, Congress passed Section 8(f) of the National Labor Relations Act in 1959. 29 U.S.C. § 158(f). This portion of the Act provided that construction industry employers may recognize unions prospectively. Id. Specifically, Section 8(f) provides:
It shall not be an unfair labor practice ... for an employer engaged primarily in the building and construction industry to make an agreement covering employees engaged ... in the building and construction industry with a labor organization of which building and construction employees are members ... because (1) the majority status of such labor organization has not been established ... or (2) such agreement requires as a condition of employment, membership in such labor organization ....
Id.
As we explained in
Goodless II,
“[ujnder Section 8®, a construction industry employer may enter into a relationship with a union whereby the union bargains on behalf of the employer’s employees pri- or to a showing that the union has gar
*105
nered the support of a majority of the employees.”
Goodless II,
Reрresentatives designated or selected for the purposes of collective bargaining by the majority of the employees in a unit appropriate for such purposes, shall be the exclusive representatives of all the employees in such unit for the purposes of collective bargaining in respect to rates of pay, wages, hours of employment, or other conditions of employment. ...
29 U.S.C. § 159(a). “Under Section 9(a), once a union has become the representative of a majority of the employees in an appropriate bargaining unit, the employer is required to bargain with the union as the employees’ bargaining representative.”
Goodless II,
Unions are often eager to convert a Section 8(f) relationship into a more permanent Section 9(a) relationship. The precise requirements for converting a Section 8(f) into a Section 9(a) relationship have been delineated in many NLRB precedents:
The NLRB has held that Section 8(f) status may change to Section 9(a) status by virtue of either a Board-certified election or as the result of the employer’s voluntary recognition of the union as the majority collective bargaining agent. Voluntary recognition requires the union’s unequivocal demand for, and the employer’s unequivocal grant of, voluntary recognition as the employees’ collective bargaining representative based on the union’s contemporaneous showing of majority employee support.
Id.
(citing
James Julian, Inc.,
B. Factual Background
The background facts of the case are essentially undisputed. They have been summarized in
Goodless II,
Goodless and the Union established a Section 8(f) relationship in 1988, from which either Goodless or the Union could withdraw upon giving 150 days notice. By 1990, the economy in the region began to falter and Goodless sought relief from certain provisions of the agreement in order to keep its business competitive. In June, 1992, Goodless indicated to the Union that “any relationship between Goodless and the Union would expire as of June 30, 1993.”
The next month, the Union threatened to cut off “target money” to Goodless if it failed to sign a “letter of assent” affirming its Section 8(f) relationship. 2 The letter included the following language:
The Employer agrees that if a majority of its employees authorize the Local Union to represent them in collective bar *106 gaining, the Employer will recognize the Local Union as the NLRA [National Labor Relations Act] Section 9(a) collective bargaining agent for all employees performing electrical construction work within the jurisdiction of the Local Union on all present and future jobsites.
Leon Goodless signed the letter on behalf of Goodless on July 15,1992.
Almost a year later, Goodless and the Union discussed the possibility of extending Goodless’s Section 8(f) relationship with the union beyond the original June 30, 1993 termination date. When negotiations stalled, the Union’s business agent, Douglas Bodman, held a meeting of all Goodless employees. He encouraged them to “sign authorization cards as evidence of their desire for continued representation,” and all did so. The cards stated:
I authorize Local Union No. 7 of the International Brotherhood of Electrical Workers to represent me in collective bargaining with my present and future employers on all present and future job-sites within the jurisdiction of the Union. This authorization is non-expiring, binding and valid until such time as I submit a written revocation.
Goodless II,
At the end of 1993, Goodless again indicated its desire to terminate its relationship with the Union. The Union responded (via letter) on December 21, 1993, сlaiming that the letter of assent signed on July 15, 1992, bound Goodless to recognize the Union as the exclusive bargaining agent if a majority of its employees authorized the Union to represent them in collective bargaining. The Union claimed to have demonstrated majority support at the June 25, 1993, meeting, and therefore alleged that Goodless could neither repudiate its collective bargaining relationship with the Union nor negotiate directly with its employees.
Goodless ignored the letter and ceased recognizing the Union for collective bargaining purposes as of January 1, 1994. Contending that it had achieved Section 9(a) status, the Union complained to the NLRB that Goodless had engaged in unfair labor practices. 3
As noted, the Administrative Law Judge who first heard the case ruled in favor of Goodless.
See Goodless I,
*107 II.
In deciding whether our decision in Goodless II permitted the Board’s decision in Goodless III, we first explain briefly the law of the case doctrine. We next summarize the law of this case as set forth in Goodless II. We then exрlain the Board’s flawed understanding of that law in Good-less III.
A. The Law of the Case
The doctrine of the law of the case “posits that when a court decides upon a rule of law, that decision should continue to govern the same issues in subsequent stages in the same case.”
Arizona v. California,
Although the Board adheres to a policy of nonacquiescence
4
in its application of decisions of the courts of appeals, it recognizes as it must that it cannot ignore the law of the case doctrine. Indeed, in
Good-less III,
the Board said that, “[h]aving acсepted the court’s remand, we are bound by the law of the case established in the court’s opinion.”
Goodless III,
B. The Law of This Case
In reversing the Administrative Law Judge’s finding that Goodless had committed no unfair labor practices, the Board decided that the Union became the Section 9(a) bargaining representative of Good-less’s employees when it presented the signed cards to Leon Goodless on June 25, 1993. Finding that “the letter of assent [signed by Leon Goodless on July 15,1992] constituted, for thе remainder of its term, both a continuing request by the Union for 9(a) recognition and a continuing, enforceable promise by [Goodless] to grant voluntary recognition on that basis if the Union demonstrated majority support,”
Goodless I,
On appeal, we determined “that the NLRB misapplied its own precedent.”
Goodless II,
Thus, in Goodless II we held that “Good-less did not violate Section 8(a)(5)” in refusing to recognize the union. Id. at 331. We announсed that “a finding in favor of Goodless is required.” Id. at 330. We ended the opinion with the following order: “For the foregoing reasons, we reverse and remand to the National Labor Relations Board for proceedings in accordance with this opinion.” Id. at 331.
C. The Board’s Decision on Remand (Goodless III)
On remand, the Board again found that Goodless had engaged in unfair labor practices. The Board asserted that “a union’s performance of the valid majoritarian conditions specified in a prospective 9(a) rеcognition clause ... is, in effect, a third option, in addition to the ‘two option[s]’ that the court identified as the only available options for achieving 9(a) status.”
Goodless III,
Despite the Board’s reliance on these other precedents, the Board’s reasoning in
Goodless I
and
Goodless III
is structurally identical: in both decisions, the Board focused on the legal significance of the letter of assent that Goodless signed on July 15, 1992.
Goodless I
held that the letter constituted a standing offer to recognize the union because of basic contract law princiрles;
Goodless III
stated that the letter was equivalent to a “prospective recognition agreement” upheld by the Board in settings outside the construction industry,
id.
at *6. Both decisions are at odds with
Goodless II’s
central holding: “Voluntary recognition requires the union’s unequivocal demand for, and the employer’s unequivocal grant of, voluntary recognition as the employees’ collective bargaining representative based on the union’s contemporaneous showing of majority employee support.”
See Goodless II,
Having acknowledged that it must comply with the law of the case, the Board had to explain why its “freedom of action on
*109
remand,”
Goodless III,
Board precedent, if read literally, as the court did, appeared to require that a union’s demand for 9(a) recognition, the employer’s agreement to recognize the union, and the union’s showing of majority status must all be simultaneous.
Id.
at *4 (citing
Goodless II,
As further support for its freedom of action on remand, the Board noted that
Goodless II
cited
Shaw’s Supermarkets, Inc. v. NLRB,
Other than a prohibition against saying that it was right in Goodless I for all of the reasons disapproved by us in Goodless II, the Board concluded that there was no law of the case that сonstrained its freedom of action on remand. It could simply reaffirm the result with a different rationale that met the “cogent explanation” standard. Addressing the three reasons cited by the Board for its authority to reaffirm its finding of unfair labor practices by Goodless, we explain why the Board’s reading of our decision in Goodless II is indefensible.
1. The Shaw’s Litigation
In
Shaw’s I,
the Board found that Shaw’s Supermarkets had committed unfair labor practices. We vacated that decision in
Shaw’s II,
finding that the Board’s precedents “dictate a result in Shaw’s favor” since Shaw’s conduct “lies tucked well within the boundary of the lawful.”
Shaw’s II,
We respectfully decline the court’s invitation to change extant Board law. For, with due respect to the court, we continue to believe that, under that law, conduct like that involved herein is unlawful. However, given the law of this case, we shall dismiss the complaint.
Shaw’s III,
2. The Remand
In our order at the end of Good-less II, we did not simply remand to the Board. We reversed and remanded. Although we are not suggesting that the word “reversed” has been used in court orders with unvarying meaning, we deem it significant here that the word “reverse” is defined to mean, inter alia, “to alter to the opposite in character or tendency; change completely.” Random House Webster’s Unabridged Dictionary 1647 (2d ed. 1997). The opposite result is a finding in favor of Goodless, not another finding against it on different grounds. By contrast, we did not use in our order the word “vacate,” which means “to render inoperative; deprive of validity; void; annul.” Id. at 2100. An order to vacate only wipes the slate clean, leaving the next outcome uncertain, absent other direction. We left no uncertainty аbout the proper outcome here.
Moreover, we reversed and remanded to the Board “for proceedings in accordance with this opinion.”
Goodless II,
If that is so, the Board says, why bother to remand to us if we could only dismiss the complaint against Goodless?
Goodless III,
3. “Some Cogent Explanation”
After concluding in
Goodless II
that “a finding in favor of Goodless is required,” we added that “[w]e cannot accept the Board’s departure from its own precedent in this сase in the absence of some cogent explanation, an explanation that has not been forthcoming.”
Goodless II,
III. Conclusion
In its effort to find “freedom of action on remand,”
Goodless III,
So ordered. Costs to respondent.
Notes
. The decision of the administrative law judge is reported as аn appendix to
Goodless I,
. "Target money was financial assistance provided by the Union to aid union employers in competition with non-union electrical contractors.”
Goodless II,
. Specifically, the Union charged that Good-less violated two sections of the National Labor Relations Act. See 29 U.S.C. § 158(a)(5) (providing that "It shall be an unfair labor practice for an employer ... to refuse to bargain collectively with the representatives of his employees....”); 29 U.S.C. § 158(a)(3) (providing that "It shall be an unfair labor practice for an employer ... by discrimination in regard to hire or tenure of employment or any term or condition of employment to encourage or discourage membership in any labor organization....”).
. Nonacquiescence refers to the "selective refusal of administrative agencies to conduct their internal proceedings consistently with adverse rulings of the courts of appeals.” Samuel Estreicher & Richard L. Revesz,
No-nacquiescence by Federal Administrative Agencies,
98 Yale L.J. 679, 681 (1989). The National Labor Relations Board, "more than most [agencies], has openly asserted the authority to decline to acquiesce.”
Id.
at 706. The Board is committed to pressing its own view of the law until the Board itself or the Supreme Court overrules it; it claims that piecemeal acceptance of particular circuits’ interpretations of the law would frustrate its development of a national labor pоlicy.
Id.
at 706 (citing
Insurance Agents' Int’l Union,
. For purposes of this opinion, the Shaw’s cases will be referred to as follows:
Shaw's I: Original NLRB decision.
Shaw’s II: Our decision vacating Shaw’s I and remanding it back to the NLRB for reconsideration (Shaw’s Supermarkets, Inc. v. NLRB,884 F.2d 34 , 35 (1st Cir.1989)).
Shaw’s III: Decision of the NLRB on remand (Shaw’s Supermarkets. Inc.,303 NLRB 382 ,1991 WL 113270 (1991) (Supplemental Decision and Order)).
. The Board argues on appeal that Shaw’s II also gave it the option of conceding, with an adequate explanation, that it was departing from precedent in finding Shaw's conduct an unfair labor practice, and then reaffirming its prior decision. Whether that is an accurate reading of Shaw’s II is irrelevant here. In this case, the Board insists that it did not depart from precedent on remand. Instead, it insists that it only clarified extant law.