Opinion for the Court filed by Circuit Judge ROGERS.
Can-Am Plumbing, Inc. (“Can-Am”) petitions for review of the National Labor Relation Board’s decision that Can-Am violated sections 7 and 8(a)(1) of the National Labor Relations Act (“the Act”), 29 U.S.C. §§ 157, 158(a)(1) (2000), by filing and maintaining a state court lawsuit concerning a union’s job targeting program that was preempted by the Act. Contrary to Can-Am’s view,
BE & K Construction Co. v. NLRB,
I.
In a complaint filed in the Superior Court of California on October 15, 1996, Can-Am, a nonunion construction contractor, alleged that L. J. Kruse Co., a union competitor, had underbid Can-Am on the Ascend Corporate Campus project, a private project. Can-Am claimed that Kruse’s lower bid was the result of an unlawful arrangement between Kruse and the United Association of Journeymen and Apprentices in the Plumbing and Pipefit-ting Industry of the United States and Canada, Local 342, AFL-CIO (“the Union”). Under the arrangement challenged by Can-Am — commonly called a job targeting program (“JTP”) — the Union uses a portion of its members’ dues to subsidize Kruse’s bids on construction projects in order to compete more effectively with nonunion contractors. The mechanics of the JTP are straightforward. On a particular construction project, a union employer such as Kruse will submit a request to the Union to use the JTP funds, which the Union collects from its members in the form of dues on all of its projects. For a project to be eligible for the JTP, Kruse must face competition from a nonunion contractor for the job. If the Union approves the use of JTP funds, Kruse takes the amount of the subsidy into account in submitting its bid. If Kruse wins the project, it pays the union employees the wages specified in the collective bargaining agreement, and the Union then uses JTP moneys to reimburse Kruse for the difference between the wages under the collective bargaining agreement and those listed in the bid. Can-Am’s complaint alleged that Kruse’s acceptance of the Union’s JTP moneys violates California laws regarding unfair trade practices, prevailing wage levels, and employer kickbacks from employees.
The Union, which was not a party to the lawsuit, responded by filing a charge with the Board that Can-Am’s lawsuit violates section 8(a)(1) of the Act because it interferes with protected section 7 rights. The
*148
Board’s General Counsel issued a complaint against Can-Am, and an Administrative Law Judge (“ALJ”) determined after a hearing that Can-Am’s state court lawsuit was preempted under the Board’s decision in
Manno Electric,
The Board affirmed, rejecting Can-Am’s argument that
Kingston Constructors,
332 N.L.R.B. No. 161,
II.
Section 8(a)(1) of the Act makes it unlawful for an employer “to interfere with, restrain, or coerce employees in the exercise of rights guaranteed” by section 7 of the Act. 29 U.S.C. § 158(a)(1). Section 7, in turn, protects the rights of employees to engage in union organization and “other concerted activities for the purpose of collective bargaining or other mutual aid or protection....” 29 U.S.C. § 157. In defining the scope of protected activity, the Board must ensure that the concerted activity is linked in some identifiable way to legitimate employee concerns related to employment matters.
Eastex, Inc. v. NLRB,
Can-Am principally contends that under the doctrine of Bill Johnson’s and BE & K Construction, its state court lawsuit against Kruse did not violate section 8(a)(1) because the only motive was to stop a competitor from using illegal funding, whatever its source, to undercut Can-Am’s *149 bidding on a major construction project. It further contends that the Union’s JTP is not entitled to section 7 protection because it is contrary to public policy. The Board responds that its findings and determinations were reasonable because the JTP falls within the “other mutual aid or protection” clause of section 7; consequently, the lawsuit seeking to dismantle the JTP was not only preempted but also unlawful under section 8(a)(1) because it directly interfered with protected conduct. Can-Am’s defense that the Union’s JTP is subject to the restrictions of the Davis-Bacon Act and the California Labor Code fails, in the Board’s view, because the Ascend project, which involved no federal or state funding, was not subject to those prevailing wage laws, and because the amount of JTP funds originating from public works projects was de minimis.
“Under the Supremacy Clause, U.S. Const, art. VI, cl. 2, state law is preempted when Congress has acted to ‘occupy the field,’ or when state law ‘stands as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress.’”
Washington Serv. Contractors Coalition v. District of Columbia,
The Supreme Court and the Board have added a gloss to the category of “arguably protected activity” cases: “(1) where arguably protected activity is involved, preemption does not occur in the absence of Board involvement in the matter, and (2) upon the Board’s involvement, a lawsuit directed at arguably protected activity is preempted by Federal labor law.”
Loehmann’s Plaza,
The courts “have traditionally accorded the Board deference with regard to its interpretation of the [Act] as long as its
*150
interpretation is rational and consistent with the statute.”
NLRB v. United Food 6 Commercial Workers Union,
Can-Am’s objection to the Board’s conclusion that its filing and maintenance of a state court lawsuit violated section 8(a)(1) has two prongs. First, Can-Am contends that its conduct should be evaluated under the standards set forth in
Bill Johnson’s Restaurants, Inc. v. NLRB,
Can-Am contends that
Bill Johnson’s
is dispositive here because the same First Amendment concerns are at stake. For further support, Can-Am relies on
BE & K,
in which the Supreme Court held that the Board may not find that a completed, unsuccessful lawsuit constituted an unfair labor practice where the suit was objectively reasonable and filed with the purpose of receiving the relief requested, although the Court left open the possibility
*151
that the Board might make such a finding if the lawsuit was filed solely to impose litigation costs and without regard for the outcome.
As the Board correctly points out, however, Bill Johnson’s and BE & K are not relevant here. In footnote 5 in Bill Johnson’s, the Supreme Court carved out an exception for preempted lawsuits:
It should be kept in mind that what is involved here is an employer’s lawsuit that the federal law would not bar except for its allegedly retaliatory motivation. We are not dealing with a suit that is claimed to be beyond the jurisdiction of the state courts because of federal-law preemption, or a suit that has an objective that is illegal under federal law. Petitioner concedes that the Board may enjoin these latter types of suits. Nor could it be successfully argued otherwise ....
The second prong of Can-Am’s objection to the Board’s conclusion that it violated section 8(a)(1) is based on record evidence that the Union’s JTP includes dues from state and federal public works projects. The Davis-Bacon Act, 40 U.S.C. § 276a(a) (2000), requires employers on federal public projects to pay their employees at the prevailing wage set by the Secretary of Labor, and it bars employees from refunding any portion of those wages to the employer, “regardless of any contractual relationship” between the parties. See Contractors and Subcontractors on Public Building or Public Work Financed in Whole or in Part by Loans or Grants from the United States, 29 C.F.R. pt. 3 (2002). California, like many states, has enacted a similar “little Davis-Bacon Act” covering state public works projects. Cal. Labor Code §§ 1771, 1773 (West 2002). See generally Herbert R. Northrup & Augustus T. White, Subsidizing Contractors to Gain Employment: Construction Union “Job Targeting, ” 17 Berkeley J. Emp. & Lab. L. 62, 80-84 (1996). Can-Am contends that because the Act does not protect JTPs that offend public policy, and the Union’s JTP is contrary to both federal and state Davis-Bacon laws, Can-Am’s lawsuit is not preempted under Garmon.
It is undisputed that the Union operates its JTP solely to foster employment opportunities for its members by “leveling the playing field.” Although in
Manno Elec-
*152
trie
the Board did not explicitly state whether any of the funds used in the JTP derived from federal public works projects, the decision suggests that all of the projects involved were on private sites, such as banks and department stores; the complaint did not allege that any of the money originated from public projects.
with respect to the interpretation of Davis-Bacon,” the Board concluded that it was bound to defer to these rulings. Id. at *14. It accordingly determined that the mandatory payment of JTP dues as a condition of employment on Davis-Bacon projects is inimical to public policy. Id. at *13.
Thus, under Board precedent, ordinarily a JTP is clearly protected under section 7, notwithstanding state policy to the contrary, unless it violates federal policy. Under this analysis, then, the presence of Davis-Bacon moneys in the Union’s JTP means that
Manno Electric
is not as readily dispositive as the Board suggests. The Board offers two responses in its brief. First, it maintains that the cases on which Can-Am relies are inapposite because the Ascend project was not a Davis-Bacon project, and there is no evidence that Kruse has ever worked on a Davis-Bacon Project. Even so, we fail to see, in light of circuit precedent, how this renders Davis-Bacon irrelevant. Although it may be somewhat ironic that the Davis-Bacon Act, which was enacted to benefit laborers, has been interpreted to bar them from benefit-ting themselves,
see Bldg. & Constr. Trades,
*153 Second, in further response to Kingston Constructors, the Board relies on its finding that the amount of funds received by the Union’s JTP from federal or state prevailing wage projects — “at most only 2 to 3 percent” of the JTP moneys — was de minimis, and hence a too-slender reed on which to rest state court jurisdiction. While the Board, then, did not treat the existence of such moneys in the JTP as wholly irrelevant, neither did it explain why the Davis-Bacon moneys did not affect the JTP’s legality or why the Union’s conduct in that regard was excusable. No court or administrative decision of the Board has yet defined precisely how much Davis-Bacon money may flow into a JTP before the program violates public policy. In the circumstances of this case, the Board’s conclusory determination that these moneys did not taint the JTP is inadequate to support its finding that the operation of the Union’s JTP was clearly protected conduct.
Initially, we note, the record contains no information on several relevant considerations. For example, nothing in the record indicates whether the Union was continuing to withhold dues on Davis-Bacon projects at the time Kruse submitted its bid on the Ascend project. Were there such evidence, the Union’s conduct would reflect a continued flouting of public policy. Similarly, nothing in the record indicates whether the two to three percent of unlawfully withheld dues made the difference in Kruse’s success as the winning bidder on the Ascend project. If that was the case, then the flouting of public policy redounded to the Union’s benefit. Either circumstance, presumably, could affect the Board’s determination of whether the Union’s JTP conduct is protected under section 7.
Further, the Board did not explain why the Union’s conduct did not make a difference or is excusable. Instead, the Board peremptorily dismissed the problem by finding that the amount of Davis-Bacon dues was
de minimis.
The Board has similarly treated minor violations of the Act as
de minimis, see, e.g., Jimmy Wakely Show,
As the Supreme Court has observed,
the Board has not been commissioned to effectuate the policies of the [Act] so single-mindedly that it may wholly ignore other and equally important Congressional objectives. Frequently the entire scope of Congressional purpose calls for careful accommodation of one statutory scheme to another, and it is not too much to demand of an administrative body that it undertake this accommodation without excessive emphasis upon its immediate task.
Southern S.S. Co. v. NLRB,
Finally, in addition to being cursory, the Board’s reasoning rested upon a thin evi-dentiary basis. In testimony before the Administrative Law Judge, a Union official estimated that the Union does a “small amount” of federal prevailing wage work — “[b]etween 1 and 2 percent at the very most” — and that “[p]robably 2 percent” of the Union’s work is on “[v]ery small” state prevailing wage jobs. Even assuming that there was substantial evidence to support the Board’s finding that the tainted money comprised only two to three percent of the Union’s JTP fund and therefore was
de minimis,
the Board treats the percentage amount as disposi-tive. This is not the only way to view the matter. If there were many small Davis-Bacon projects, or a few large ones over a number of years, the denominator and numerator could produce vastly different versions of the extent to which the Union flaunted public policy. The Board never explains its choice. Moreover, having treated the tainted moneys as
de minimis,
the Board provides no insight on how it views the burdens regarding the sources of commingled funds. It appears from the record that the Board views it sufficient for the General Counsel to offer evidence estimating the amount of tainted funds even when such estimation does not reflect the kind of careful consideration that the Board must undertake when treading in a realm beyond its expertise.
See Hoffman Plastic,
Accordingly, we grant the petition, deny the cross petition for enforcement of the Board’s Order, and remand the case to the Board. On remand, additional evidence may show that the Union stopped withholding Davis-Bacon dues at the time Kruse submitted its bid on the Ascend project, or, indeed, had stopped long before that time. Additional evidence may also provide support for the Board’s conclusion that the Union’s conduct is excusable or makes no difference to the Board’s section 7 determination. Thus, the Board on remand may yet determine that the JTP is protected under section 7.
