275 F.3d 1106 (D.C. Cir. 2002)
Sasol North America Inc., Petitionerv.National Labor Relations Board, Respondent
No. 00-1525
United States Court of Appeals FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued December 5, 2001Decided January 8, 2002Corrected January 25, 2002

Petition for Review and Cross-Application for Enforcement of an Order of the  National Labor Relations Board
James P. Gillece Jr. argued the cause for petitioner.  With  him on the briefs was Robert R. Niccolini.
Siobhan M. Kelly, Attorney, National Labor Relations  Board, argued the cause for respondent.  With her on the  brief were Arthur F. Rosenfeld, General Counsel, John H.  Ferguson, Associate General Counsel, Aileen A. Armstrong, Deputy Associate General Counsel, and Frederick C. Havard,  Supervisory Attorney.
Before:  Sentelle and Rogers, Circuit Judges, and  Williams, Senior Circuit Judge.
Opinion for the Court filed by Senior Circuit Judge  Williams.
Williams, Senior Circuit Judge:


1
Sasol North America, Inc.  (formerly known as Condea Vista Chemical Co.) appeals from  the National Labor Relations Board's ruling that it violated  various provisions of the National Labor Relations Act, 29  U.S.C.  151 et seq.  The charge:  that Sasol, inspired by  anti-union animus, had unilaterally (i.e., without affording the  union an opportunity to bargain) abandoned an unwritten  policy allowing unlimited unpaid leave for union leaders to  work on union business.  The Board found both anti-union  animus and refusal to bargain.  See Condea Vista Company,  2000 NLRB LEXIS 813, 332 NLRB No. 117 (Nov. 16, 2000). In fact, however, the Board simply assumed its starting  point--that Sasol had previously had a policy of unlimited  leave, in the sense that the Board conceived it:  leave at any  time and in any amount, so long as the leave was taken for  union activity.  Additional errors followed.  We therefore  grant the petition for review, deny the cross-application for enforcement and remand for further proceedings.


2
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3
Sasol operates a chemical manufacturing facility in Lake  Charles, Louisiana.  Its workers are represented by the  Paper, Allied Industrial, Chemical and Energy Workers International Union No. 4-555.  The collective bargaining  agreement explicitly provides that union leaders may take  reasonable paid leave:


4
22-4 Worker's Committee and Stewards shall be permitted reasonable time to investigate, present, and process grievances on [Sasol] property during their regular working hours without loss of time or pay.  Such time spent in handling grievances, or mutually agreed-upon Union business, during the Steward's alternate's or Worker's  Committee's regular working hours shall be considered working hours in computing daily and/or weekly overtime if within the regular schedule of the employee.


5
Though there is no provision in the CBA relating to unpaid  leave for union activities, such leave was commonly taken  pursuant to an unwritten policy (the exact nature of which is  at issue).


6
This case was precipitated in April 1998, when Daren  Appleby, president of Local No. 4-555 and a plant operator  (as both parties describe him, though without explanation of  his responsibilities), filed a grievance complaining that he had  not received adequate training.  Appleby's supervisors responded that Appleby had failed to receive training simply  because he was so often absent from work.


7
That claim gave rise to an internal investigation, finding  that Appleby had taken unpaid union leave from about 36% of  his scheduled work periods between January and October of  1998;  the ultimate figures for all of 1998 showed that he  missed 35% of his work periods for unpaid leave and an  additional 9.5% because of vacation and sick days.


8
This prompted Sasol to crack down on Appleby's liberal use  of unpaid leave.  In a letter dated October 30, 1998, Jim Ely  (Sasol's Human Resources Administrator) admonished Appleby that "36% absence for off-property Union business is too  much and we expect to approve less of this type in the  future."  Ely went on to say, "We will approve a reasonable  amount of Union business time for on-site Union business as  specified in Article 22-4, as possible given the nature of  Operations and Maintenance work here at CONDEA Vista,  and only with prior approval of each Committeeman's immediate supervisor."


9
In December of 1998, Appleby met with three Sasol managers:  Chris Turner, Mike Glackin, and Jim Ely.  The managers all testified that Turner brought up the issue of unpaid  leave, and Appleby responded that he did not have to talk  about that issue.  Appleby himself, when asked if anything  was said at the meeting about unpaid leave, first said, "I don't recollect," but went on to deny that he had refused to discuss  excessive unpaid leave.


10
Sasol followed up the October 1998 letter with one sent on  February 26, 1999 from Jim Ely to Appleby.  The letter said:


11
As stated previously, we will no longer be able to provide this large amount of excused time for offproperty Union-related matters.  The need to operate the plant efficiently and for all employees to stay currently trained on their job requires that all employees attend work regularly.


12
Effective March 15, 1999, we will administer Article 22-4 as written.  There is no provision in 22-4 for excused time off for Union-related matters off Company property.


13
We will approve a reasonable amount of on-site Union business time for Worker's Committee members and Stewards as specified in Article 22-4, as possible, upon advanced request, with a general description of what the time is needed for, to the employee's immediate Supervisor.


14
Characterizing this as a change in company policy, the union  replied on March 4, 1999, requesting that Sasol meet and  bargain. Sasol manager Chris Turner responded March 10,  saying:  "With respect to your alleged demand for bargaining  over this 'change,' no change is being implemented.  To the  contrary, the Company is simply applying Article 22-4 as  written."


15
An increasingly acrimonious series of letters followed between Appleby and various Sasol managers.  Perhaps from a  change of heart (or perhaps fearing impending litigation),  Human Resources Manager Mike Glackin wrote Appleby on  June 29, 1999, offering to bargain with the union over the  issue of unpaid leave. By this point, however, Appleby had  apparently lost interest in bargaining, and chose instead to  file unfair labor practice charges with the Board.  After a  hearing in January 2000, the ALJ held that Sasol had violated   8(a)(1), (3), and (5) of the NLRA, 29 U.S.C.  158(a)(1),  (3), (5).  See Condea Vista Company, 2000 NLRB LEXIS 813, at *7, 332 NLRB No. 117 (Nov. 16, 2000) (reprinting  ALJ's decision).


16
The ALJ first found that Sasol's "policy before October  1998 was to grant unpaid leave for Union business away from  its plant."  2000 NLRB LEXIS 813, at *15-*16.  The ALJ  chose to discredit (apparently as hearsay) Jim Ely's testimony that company supervisors had in the past denied requests  for unpaid union leave.  Id. at *27.


17
The ALJ then found that Sasol's change in this policy was  motivated by anti-union animus, a violation of  8(a)(3) and  (1) of the NLRA, 29 U.S.C.  158(a)(3), (1).  Id. at *22.  The  ALJ relied mainly on testimony by Gary Beevers, an international union representative.  Beevers testified that in an April  1999 meeting with Mike Glackin and Jim Ely, Glackin had  said that the suspension of unpaid union leave was because  Appleby "was using that leave to prepare untrue Union  leaflets ... and frivolous complaints with the NLRB and  numerous data demands."  Id. *16-*17, *20-*21.  Glackin  denied this version of their meeting, but the ALJ credited  Beevers's testimony, apparently relying substantially on Glackin's notes of the meeting.  Id. at *16-*17.


18
Sasol offered a defense under Wright Line, 251 NLRB  1083 (1980), enf'd 662 F.2d 899 (1st Cir. 1981), saying that it  would have taken the same action regardless of any alleged  anti-union animus.  It reasoned that Appleby's extended periods of absence were an "abuse" of the unpaid leave policy,  and that such absences resulted in a lack of adequate job  training, thus threatening the safety of operations at Sasol's  plant.  The ALJ, however, reconceived the concept of "abuse"  as limited solely to whether Appleby's union leaves had been  for personal business, id. at *21-*22, evidently assuming that  Sasol could not regard leave as "abusive" merely because it  prevented the worker from performing necessary functions  (here, as Appleby's grievance had highlighted, attending safety training).  Having so narrowed the abuse inquiry, the ALJ  concluded that Sasol failed to establish its Wright Line  defense.  Id. at *22.


19
The ALJ then found that Sasol had violated  8(a)(5) of the  NLRA, 29 U.S.C.  158(a)(5), by failing to bargain with the  union before changing its unpaid leave policy.  Id. at *22-*23  (citing NLRB v. Katz, 369 U.S. 736, 745-47 (1963)).  In  reaching this conclusion it held that neither of the two main  exceptions to a company's duty to bargain was present in this  case:  the union's use of dilatory tactics to avoid bargaining,  or economic exigencies demanding immediate action.  Id. at  *28-*29 (citing International Paper Company, 319 NLRB  1253, 1273-74 (1995)).


20
Following the filing of exceptions by both parties, the  Board adopted the ALJ's decision in full.  Condea Vista  Company, 2000 NLRB LEXIS 813, 332 NLRB No. 117 (Nov.  16, 2000).  In addition, the Board noted that Mike Glackin  had allegedly told Gary Beevers that unpaid leave was to be  canceled in part because of the union's "frivolous complaints  with the NLRB."  Because there was no evidence of any  frivolous complaints, the Board found that Sasol had violated   8(a)(4), 29 U.S.C.  158(a)(4) (penalizing discrimination  "against an employee because he has filed charges ... under  this subchapter").  Id. at *2 n.4.


21
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22
We think that the Board erred on three crucial issues: whether Sasol changed its unpaid leave policy;  whether Sasol  acted out of anti-union animus;  and whether Sasol presented  a valid Wright Line defense.


23
The Board maintains that before the Appleby episode Sasol  allowed unlimited unpaid leave, which is why it required Sasol  to post a notice saying that it would not "change our policy of  granting unlimited unpaid leave...."  2000 NLRB LEXIS  813 at *38.  And the Board's lawyer at oral argument admitted that, in the Board's eyes, Sasol's policy would have  allowed a union official to spend 95% of his working time  tending to union affairs.


24
Not only is there no substantial evidence to support this  interpretation of Sasol's unpaid leave policy, there is no  evidence whatever in the record before us.  The Board relied on the fact that Appleby took a "substantial amount of unpaid  leave for union business during 1997 and 1998."  But Sasol  tried to limit Appleby's leave to something more reasonable  as soon as his extended absences came to its attention;  the  mere fact that Appleby got away with lavish leave for a year  or so does not establish that there was ever a general policy  of unlimited leave.


25
The Board argues that Sasol had never before claimed that  a "union official had abused the policy by taking too much  unpaid leave."  Respondent's Br. at 19.  But, as the Board's  lawyer admitted, there is no evidence that any other union  official ever tried to take 36% of his time in unpaid leave.  It  is hard to imagine that a rational firm would ever, absent  very substantial concessions by the union, agree to a leave  policy as unlimited as the Board assumed.  To assert that  Sasol had a policy of unlimited leave requires at least some  evidence--and the Board has none.


26
One might think that even if the leave policy had been  short of "unlimited," Sasol might be liable for a unilateral  change if, without bargaining, it eliminated unpaid leave  altogether.  But the evidence on Sasol's conduct is unclear,  and neither the ALJ nor the Board ever found that Sasol  changed from a policy of reasonable unpaid leave to none at  all.  It is questionable whether substantial evidence would  support any such finding.


27
Sasol's letter of February 26, 1999--which the Board's  brief characterizes as having "terminate[d]" unpaid leave-never even refers to a distinction between paid and unpaid  leave.  Rather, it says that Sasol will no longer provide leave  for "matters off Company property"--apparently whether  paid or unpaid.  Instead, "Effective March 15, 1999, we will  administer Article 22-4 as written."  The effect of this statement on unpaid leave is murky, since Article 22-4 doesn't  mention unpaid leave at all.  Sasol might have meant that  since Article 22-4 is silent on unpaid leave, it would henceforth never permit such leave.  Alternatively, it might have  meant that unpaid leave would be limited by a criterion of  reasonableness--as Article 22-4 provided in the case of paid leave.  Sasol (through its lawyer and its managers' testimony)  seemed generally to have envisioned a policy of reasonable  unpaid leave, consistent with the latter reading.  See, e.g.,  Joint Appendix 18, 19, 82, 101, 116, 134-36, 161, 270-71, 510; but compare id. 52, 71, 91, 92, 98, 99, 100, 109, 263.


28
Indeed, one of Sasol's exceptions to the ALJ's ruling was  that the ALJ failed "to find that the reasonable limitations  placed upon unpaid union leave by Condea Vista mirrored  and tracked the reasonable limitations placed on paid union  leave pursuant to Section 22-4...."  Absent a finding on the  point supported by substantial evidence, we cannot affirm the  Board's order on an assumption Sasol actually changed its  unpaid leave policy, as opposed to merely enforcing a preexisting reasonableness criterion.


29
Next, we think the Board erred in its conclusion that Sasol  acted out of anti-union animus.  The evidence for this conclusion is paltry at best.  The ALJ first relied on Jim Ely's  October 30, 1998 letter saying that Appleby's leave time was  " 'too much and we expect to approve less of this type in the  future.' "  After quoting this letter, the Board states that  "Appleby and other Union officials were engaged in protected  activity when handling Union business."  Condea Vista, 2000  NLRB LEXIS 813, at *20.  Though no argument is spelled  out here, the implication is that because Appleby was taking  time off for union activities, Sasol could have no motivation  for limiting his leave other than to curtail the union activities. But this would make sense only on the Board's assumption  that Sasol had a policy of totally unconstrained union leave-an assumption without any basis.  Just as an employee  cannot "shield himself from all possibility of termination  merely by becoming a union activist," Synergy Gas Corp. v.  NLRB, 19 F.3d 649, 652 (D.C. Cir. 1994), neither can a union  official--absent a bargain to that effect--shield himself from  ever having to show up for work merely by conducting union  business.  And, as we discuss in more detail below, Sasol  made it clear on numerous occasions--both in discussions  with the union and in testimony before the ALJ--that it  thought Appleby's continued absences were unreasonable.


30
The second (and last) piece of evidence for anti-union  animus is an account of the April 1999 meeting between Mike  Glackin, Jim Ely, and international union representative Gary  Beevers.  As noted above, Beevers testified that Glackin said  that the unpaid leave policy was to be revoked because  Appleby had used his time off to prepare untrue union  leaflets, frivolous complaints with the NLRB, and numerous  data demands.  Glackin, for his part, said that "Mr. Beevers  either made an untrue statement, or Mr. Beevers clearly  misunderstood something that I said."  The ALJ resolved the  conflict in favor of Beevers, explaining that Glackin's own  handwritten notes of the meeting "tend to support the testimony of Beevers."  Condea Vista, 2000 NLRB LEXIS 813, at  *17, *21.  This support allegedly comes from two sentences in  the Glackin notes:  "I pointed out the examples of the Union  grieves and arbitrates every issue, that they have filed numerous info requests which are frivolous and harassment...." and "I further mentioned a charge that Jim Ely  had threatened the lives of Ray Reynolds and his family and  then would not allow me to properly investigate the charges,  is another example of the Union not Mgmt. straining the  possibility of establishing a better working relationship." J.A. 507, 508;  2000 NLRB LEXIS 813 at *17.


31
But the ALJ's use of the Glackin notes was palpably  defective.  The two statements relied on by the Board appear  in the part of Glackin's notes describing his and Beevers's  discussion of the union/management relationship in general,  not the leave policy.  J.A. 507-08.  Two pages later the notes  recount the parties' discussion of unpaid leave.  They report  that Glackin told Beevers that the issue arose because Appleby filed a grievance for insufficient training, and Appleby's  supervisors said that "he's never here @ work and they have  a big concern about him keeping current...."  J.A. 509. Thus, contrary to the ALJ's view, Glackin's notes do not  support the idea that he told Beevers that the leave policy  was changed because of objections to the content of union  activity.  In context, the two statements recorded by Glackin  do not even remotely constitute evidence of a "threat of  reprisal or force or promise of benefit," 29 U.S.C.  158(c);  under that provision, therefore, they cannot be used as "evidence of an unfair labor practice under any of the provisions"  of the NLRA.  Id.;  see also Medeco Security Locks, Inc. v.  NLRB, 142 F.3d 733, 744 (4th Cir. 1998);  BE & K Constr. Co.  v. NLRB, 133 F.3d 1372, 1375-77 (11th Cir. 1997);  HoloKrome Co. v. NLRB, 907 F.2d 1343, 1345-47 (2d Cir. 1990); Ross Stores, Inc. v. NLRB, 235 F.3d 669, 676 (D.C. Cir. 2001)  (Henderson, J., concurring).  While an agency's credibility  decision normally enjoys almost overwhelming deference, it  does not do so when it rests explicitly on a mistaken notion. See, e.g., United States ex rel. Exarchou v. Murff, 265 F.2d  504, 507 (2d Cir. 1959) (agency credibility decision reversible  where based simply on mistaken view of the story's plausibility).


32
Given the Board's mistaken understanding of the Company's unpaid leave policy and its misplaced reliance on Glackin's notes, its finding that Sasol's policy was driven by antiunion animus is unfounded.  See Southwest Merchandising  Corp. v. NLRB, 943 F.2d 1354, 1361 (D.C. Cir. 1991) (Board  failures in reasoning prevent review for substantial evidence).


33
Finally, we find no justification for the short shrift the ALJ  gave Sasol's Wright Line defense--its argument that it would  have taken the same action (whether characterized as change  or as enforcement) regardless of any alleged anti-union animus.  The ALJ treated this solely as a claim that Appleby  was using his union leave for personal rather than union  business.  2000 NLRB LEXIS 813 at *21.  Sasol did raise  that narrow claim, and we'll assume the ALJ's rejection was  supported.  But Sasol also raised the general point that  Appleby's lengthy absences constituted an "abuse" of its  policy, see J.A. 91, 99, 113, 125-26, 158, 165, 174-75, and the  specific argument that the extended absences caused a lack of  current training, in turn leading to increased safety risks, see,  e.g., J.A. 113, 160, 166.  Sasol's February 1999 letter made  the point explicitly, asserting the "need to operate the plant  efficiently and for all employees to stay currently trained on  their job [sic]."  Again, we need not decide on the validity of  these "obvious alternative explanations," Southwest Merchandising Corp., 943 F.2d at 1361, as the Board never even considered them.  The Wright Line defense is therefore yet  another issue the Board must consider on remand.  Cf.  McQuaide, Inc. v. NLRB, 133 F.3d 47, 50 (D.C. Cir. 1998). Of course, "[t]he weaker a prima facie case against an employer under Wright Line, the easier for an employer to meet  his burden ... of proving that the [employer's action] would  have occurred regardless of the protected activity."  Hartley  v. NLRB, 669 F.2d 579, 582 (9th Cir. 1982).


34
Finally, we cannot sustain the Board's finding that Sasol  violated 29 U.S.C.  158(a)(5) by failing to bargain before  "changing" the unpaid leave policy.  Because it is impossible  to say whether there was substantial evidence of any such  change, it is premature to consider the issue of breach of the  duty to bargain.


35
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36
We grant the petition for review, deny the cross-application for enforcement, and remand the case ot the Board for further proceedings consistent with this opinion.


37
So ordered.

