delivered the opinion of the court:
In
Beckham
v.
United States,
Plaintiff was retired from the Army for years of service. Though he allegedly requested, prior to retirement, that he be evaluated for service-comiected physical disability, he has never appeared before a Physical Evaluation Board. His two applications for relief to the Army Board for the Correction of Military Records were denied, without a hearing, in summary statements of rejection. 2 The administrative record consists of Army records and the written materials which *503 plaintiff furnished to the Correction Board in asking for a hearing. After this suit was filed and the case referred to the trial commissioner, the defendant filed a motion to preclude the introduction of de novo evidence, which the commissioner denied on the authority of Bechham. The Government requests review of that ruling.
The customary rationale of the limited scope of judicial review of agency determinations is that deference should be accorded the judgment of an administrative decision-maker, either because the legislature granted it a measure of discretion on facts or policy, or because of the agency’s expertise in handling the subject matter. Most often, this leads to confining court intervention to instances in which the administrative decision was arbitrary and capricious, inconsistent with applicable statutes or regulations, or unsupported by substantial evidence. E.g., K. Davis, AdmiNistrative Law Treatise § 29.01 (1958).
Since Congress has vested the Service Secretaries (acting on the recommendation of the various physical disability
3
and correction boards) with such discretion in determining eligibility for disability-retired pay, we have always adhered to that scope of review.
4
We have also, since we first began dealing with disability retirement two decades ago, regularly considered evidence over and above that presented before the administrative boards if a party wishes to offer it. See Appendix, infra, for a list of cases which is not exhaustive. This practice has prevailed over the years, with only sporadic objection and with no real deviation by the court.
5
This coupling of the substantial-evidence standard
*504
with the acceptance of new evidence has not, in the view we have expressed, encroached on the administrative process. As we put it in Beckham,
In reviewing [Correction] Board decisions [or decisions of the other boards] this court has not substituted its judgment for that of the Board. Only where the decision of the Board is arbitrary, capricious, or unsupported by substantial evidence has this court interfered with the findings of the Board. * * * [W]e ask if the decision meets the test when compared with all available evidence — that is both the [administrative] record and the de novo evidence.
I.
The Government’s main position is that this ingrained procedure in the military disability-retirement field is proved wrong by the Supreme Court’s ruling in
United States
v.
Carlo Bianchi & Co.,
The problem now before us is quite different. The Wunder-lich Act, of course, has no application to disability-retirement cases. And the statutes granting disability-retirement pay (10 U.S.C. §§1201, 1204, 1210, 1215, 1401 (1964)) and authorizing the creation of the disability-retirement boards (10 U.S.C. §§1214, 1216, 1554 (1964)) and Correction Boards (10 U.S.C. §1552 (1964)) do not refer to judicial review, much less to the procedure to be used on review. 7 Nor is there any other indication that Congress, at any time, intended to restrict our consideration to the evidence before the administrative bodies. The issue cannot be resolved by searching for an actual legislative intention.
The Government recognizes this, but says that nevertheless
Bianchi
lays down the overriding doctrine that, whenever an agency determination is to be tested by the standard of arbitrariness and substantial evidence, the administrative record cannot be augmented. But the Court’s statement that the substantial-evidence test “goes to the reasonableness of what the agency did
on the basis of the evidence before
it”
*506
(
Though judicial review limited to the evidence adduced before the agency is the usual practice, there are exceptions, comparable to our own, in which the courts have deferred to the decisions and findings of an administrator while allowing the parties to introduce evidence that may or may not have been presented at the administrative level. The most common in the federal system are civil actions to obtain patents or to contest a Patent Office interference determination, 8 and tax suits, the latter including cases in which de novo evidence is offered to prove that the Commissioner of Internal Kevenue abused discretion specifically delegated to him, as well as cases in which the taxpayer seeks to overcome the general presumption running in favor of the Revenue Service’s assessments. 9
In other fields, a number of courts adhering to a standard of judicial review similar to that we apply in disability-
*507
retirement cases have utilized extra-administrative record evidence. See,
e.g., Jordan
v.
United Ins. Co. of America,
We cite these instances not as controlling precedents but to indicate that the question of allowing d& novo evidence in a particular kind of case — especially where, as here, the statute is silent — is to be determined by an evaluation of the individual factors converging on the problem of review in that specific kind of suit. See L. Jaffe, judicial coNtbol of admiNxsteative action 619-23 (1965). If Congress has not spoken, there is no mechanical or reflex solution. The result should depend, not on the quotation of a broad general rule, but on the insight gained from a hard look at the judi *508 cial function vis-a-vis tbe administrative role in tbat particular category of case. 12
II.
The initial decision on a serviceman’s entitlement to disability retired pay is theoretically made by tbe Secretary of Army (or other Service).
E.g., Heins
v.
United States,
The nature of the administrative record varies with the
*509
process the claimant receives. He is not guaranteed a hearing. While 10 U.S.C. § 1214 (1964) mandates a “full and fair” hearing for a member of the armed services before separation for physical disability, he may be (and often is) separated for reasons other than disability
(e.g.,
longevity) without a hearing even though he believes he is entitled to disability-retirement pay. See
Wales
v.
United States,
The void is not filled by the Correction Board, whose regulations specifically authorize denial of applications without formal hearing (32 C.F.R. § 581.3 (c) (5) (1968)), and which need not be resorted to at all if a Physical Evaluation Board hearing was previously refused. As in the present case, the frequent result is that the only real hearing available in a disability retirement case is a ‘judicial hearing. 14 In those cases the administrative record consists, as here, simply of the official military records plus the written materials (e.g., medical statements, post-discharge medical records, etc.) the claimant has seen fit to furnish in connection with his request for relief by the Physical Evaluation or Correction Board. There is no oral testimony, no examination of witnesses or cross-examination, and, aside from official records, a minimal presentation of the case against allowance of disability retirement pay. The administrative “findings” are formal and summary, indicating no more than that relief is not warranted. See note 2 supra.
If the serviceman is granted a hearing by one or another board, he does have the right to offer evidence and to probe the evidence, such as it is. See 32 C.F.B. §§ 581.3 (d)-(e)
*510
(1968); Army Regs. 635-40A ¶¶16; 22, and 635-40B ¶¶16 (a), 18, 20, 24, 27. But the service need not produce live witnesses ; it can, and most often does, rely on records and written statements and materials. In fact, no provision is made for a representative of the service to oppose the claim. Instead the boards themselves call for and examine evidence. At the Physical Evaluation Board level, a recorder is appointed to “make a full and impartial presentation” of the evidence (Army Reg. 635-40A ¶ 15), and both the Correction Board and Physical Review Council have authority to request advisory opinions from other service officials, including The Surgeon General (32 C.F.R. § 581.3 (f), (h) (1968); Army Reg. 15-160 ¶ 8; see,
e.g., Wood
v.
United
States,
As this recital shows, the most important operational characteristic of both the Correction Board and the Physical Evaluation Board (as well as the latter’s appellate bodies) is that their function is to
investigate
the possibility that a serviceman is suffering from a service-connected disability. They do not sit as tribunals adjudicating disputes between adverse parties, and they do not have the procedures of such tribunals. The Supreme Court observed, in connection with the Army Disability Review Board, that the hearings provided “are not contests; they are inquiries concerning disability. The purpose is to get at the truth of the matter.”
Robertson
v. Chambers,
Consistent with the investigatory nature of the administrative function is the Correction Board’s practice of accepting
*511
de novo
evidence (or written materials) even though, the applicant was accorded a full hearing before a Physical Evaluation Board (PEB). See,
e.g., Davis
v.
United States,
It is also a significant factor (see Part III infra) that the Secretary of the Army has chosen to exercise the broad range of discretion that Congress gave him by promulgating specific substantive regulations. See Army Regs. 635-40C and 40-501 ch. 3. 16 In addition, both the Secretary and the boards are now bound by statute to follow the detailed guidelines of the Veterans’ Administration’s disability code when determining the percentage of disability under the Career Compensation Act. See 10 U.S.C. §§1201, 1203-04, 1206 (1964). Consequently, the boards have little latitude for developing general retirement policies in individual cases. Their job is to pass upon a particular case under the standards handed down to them.
III.
The character of the administrative process in military disability-retirement cases, as we have just Outlined it, strongly suggests the propriety of our established practice of accepting de novo evidence in this area. On the one hand, the administrative system, as a whole, is not designed to collect and evaluate for itself all the evidence bearing on the issue of *512 disability, nor is it geared to produce records comparable to those of the regulatory agencies. There is, in short, less need and less warrant for deferring to the administrative fact-finding process, as all-inclusive, self-contained, and final. On the other hand, the administrative system is such that court intervention, by way of the augmentation of evidence, will interfere much less with the carrying on of this administrative function than is true for many other administrative bodies.
First, as to the fact-finding process and the records. We have pointed out that normally the records do not reflect adversary hearings, with the testing and evaluation typical of that kind of process. In many, possibly most, of the cases coming here no administrative hearing was held at all, and the administrative record, as in this case, is simply a miscellaneous collection of materials presented by the claimant and, to a much less extent, by the service. The actual, as well as the potential, lacunae need not be elaborated. The evidence we have considered to fill these gaps has been, in the vast majority of instances, expert medical testimony. 17 We have also accepted evidence for the purpose of filling in the post-separation medical, social, and economic history of the plaintiff, 18 of explaining omissions in the plaintiff’s medical records, 19 and of detecting latent irregularities in the administrative proceedings. 20 This evidence has proved invaluable in fully understanding and evaluating the basis — or lack of basis — for the administrative decision.
*513
It is plain, we believe, that non-adversary records of the kind we have in this case and which come before us in a large segment of these cases cannot form the sole basis for a judicial decision. They are too infirm and incomplete. Our remedy, for about a generation, has been to permit the parties to augment the evidence, and then for us to apply the customary standards of review to the entire record. As shown in Part I
supra,
though that is not the usual method of scrutinizing administrative decisions, it is by no means unique, especially for non-adversary records of this kind. See
Jordan
v.
United Ins. Co. of America, supra,
Two other solutions can be suggested for the difficulties created by the administrative scheme, but we think that neither of these proposals is as appropriate as the course we have followed; at the least, they are not so convincing as to press us at this stage to change our long-established practice. Possibly we could say that, where there has been a full-scale administrative hearing, 21 we will not receive de novo evidence, reserving that procedure for instances, like this, in which an administrative hearing was not held. This remedy would have the unsatisfactory sequel of requiring us, in each case, to evaluate the record preliminarily in order to decide whether in fact a full-scale hearing was held. Since the various administrative records in this field run the gamut, there would be considerable opportunity for dispute and the parties would no doubt disagree often on that initial issue. We would thus be faced, at the outset, with deciding a burdensome and time-consuming threshold controversy before the case could even begin to be considered on its merits.
Moreover, as we noted in Part II supra, the Correction Board can and does accept additional evidence not offered to the Physical Evaluation Board (or its appellate tribunals) even where a full hearing has already been had before those bodies. In cases coming here directly from the PEB (or the disability review boards), without going to the Correction *514 Board, only this court can perform the function of taking account of new evidence. If we refuse to do so and decide only on the administrative record, the claimant is put at a disadvantage. In any event, we have the problem that in this field even the “full” hearings are ordinarily not trial-type since written statements are often considered and their authors not subject to examination. It might well be that many records of this kind could not be accepted as adequate. See Part IV infra.
Alternatively, it would be possible, where a proper hearing was not held, to suspend proceedings and allow the plaintiff to return to the Army for such a hearing if we thought one should have been had. This course would raise the same obstacle of compelling us to make a preliminary determination in a large number of cases. We have pointed out that, unlike the contract “dispute” cases, many disability-retirement cases come to us without any hearing; the problem of a preliminary examination would be routine, not exceptional (as it is for contract cases). Then, if a case were sent back the claimant could face difficulties due to the ad hoc nature of the Physical Evaluation Boards, 22 and, at any rate, the hearing afforded would not be adversary, with the right to cross-examine all opposing witnesses (because of the acceptance of written statements and consideration of untested communications within the service) —as is now normal for the regulatory agencies and the boards of contract appeals. 23
Our established practice is also supported, and the case for
*515
the substitute remedies weakened, by the difference in impact of the receipt of
de novo
evidence on the functioning of these service boards, as contrasted to better known administrative bodies (the regulatory agencies and the contract appeal boards). Here, as we have stressed, we deal, not with adversary process, but with continuing administrative “inquiries” designed “to get at the truth of the matter.” The Correction Board, for example, receives new evidence despite a full hearing before a PEB. This investigatory, nonadversary format means that it is less wrenching for a court to augment the evidence than it would be for truly contested proceedings where the administrative tribunal cannot fulfill its dispute-settling function unless the parties are forced to raise and settle all issues before it. This was a problem, in Congress’s eyes, with the procedures for disposing of Government contract disputes before the “Wunderlich Act. See
United States
v.
Carlo Bianchi
&
Co.,
supra,
Similarly, the possibility of duplication of evidence is less than in the other types of administrative review. Ordinarily in these cases the court evidence has not been presented previously at all, or not in testimonial form subject to cross-examination. It is not our feeling that there has, in fact, been much actual duplication. Bather, the de novo evidence has generally been new to the case, not merely to the court. At *516 present, if the parties in this court have nothing new to add, they normally both rest on the administrative record. If that is not done and the Government believes that a de novo trial will truly be a duplication of a prior hearing, it can move for summary judgment on the administrative record, suggesting that the claimant proposes to offer nothing new. If that is so, we are and would be hospitable to a disposition of the case on the existing record. Duplication of hearings is being, and can be, avoided without excluding evidence which is far from repetitive.
A separate, though related, reason for thinking that
de novo
evidence in this corner of the law is not harmful to the administrative process, as it is in other fields, is that these military boards do not set policy but make their determinations within narrow bounds. Kegulatory agencies frequently exercise their discretion by formulating broad policies in individual cases. Cf.
Securities & Exchange Comm’n
v.
New England Elec. Sys.,
As indicated in Part II
supra,
the administrative regulations make it unlikely that an individual case will be the springboard for a major policy pronouncement, and compliance with these regulations ensures uniformity of treatment.
*517
When we review a particular board decision the regulations usually control what conclusion must be drawn from any new evidence produced at trial. The chances are slim that we will have to assess the implications of that evidence for other disability cases. This aspect of disability-retirement cases “minimize[s] the opportunity for reviewing courts to substitute their discretion for that of the agency”
(Consolo
v.
Federal Maritime Comm'n,
IV.
These are the reasons sustaining our consistent practice of not barring de novo evidence in military disability-retirement cases. They are reasons bolted to the particular machinery of this administrative operation. We think that the usage has worked well for two decades, without harm to the interests of claimants or of the Government. It has given due deference to the administrative decision, through the standard of review we have applied, without scanting the claimant’s procedural rights or the defendant’s opportunity to explain and support the board ruling.
We could, we suppose, have taken the other road when we first began to get these cases in the 1940’s. If we had, the course of our rulings — given the nature of the administrative records and of the particular administrative process — would probably have pressed the services to afford fuller, adversary, more trial-type hearings,
25
and in a larger proportion of the cases, and also to prepare more extensive opinions and factual findings. Cf.
Lloyd Sabaudo Societa Anonima per Azioni
v. Elting,
The trial commissioner’s order denying the defendant’s motion to preclude de novo evidence is affirmed, and the case is remanded to the commissioner for further proceedings.
APPENDIX
Military Disability Retirement Oases In Which De Novo Evidence Has Olearly Been Admitted
Russell
v.
United States,
Notes
After the Government’s petition for certiorari was filed, the plaintiff re-guested that our order remanding the case to the trial commissioner be withdrawn and that the case be decided solely on the administrative record. An order to this effect was entered in November 1967, and shortly thereafter the parties stipulated the dismissal of the petition for certiorari under Sup. Ct. Rule 60,
The Correction Board simply informed plaintiff that insufficient evidence had been presented to indicate probable material error or injustice, and that no material evidence of error or injustice was shown to warrant granting a formal hearing. This is the usual form when a hearing is denied.
These include the Physical Evaluation (formerly Retiring) Boards, Physical Review Councils, and Physical Disability Review or Appeal Boards. See generally
Harris
v.
United States,
E.g., Hoffman
v.
United States,
So far as we can now tell, the only cases prior to
Bechham
in which the Government appears to have objected generally to the admission of
de novo
evidence were
San Millan
v.
United States,
The misgivings in other cases seem to have been related only to the probative value of the evidence proffered by the plaintiff. See
Kingsley
v.
United States,
The defendant also relies on
Towell
v.
United States,
National Broadcasting Co.
v.
United States,
See
Friedman
v.
United States,
See,
e.g., California Research Corp.
v.
Ladd,
An applicant for a patent or both parties to an interference may waive the right to a civil action and appeal to tbe Court of Customs and Patent Appeals. See 35 U.S.C. § 141 (1964). That court bears and determines the appeal “on tbe evidence produced before tbe Patent Office.” 35 U.S.C. § 144 (1964).
See,
e.g., Helvering
v.
Taylor,
See,
e.g., In re Topper,
See,
e.g., Powell
v.
Brannan,
Lloyd Sabando Societa Anonima per Azioni
v.
Elting,
Consolo
v.
Federal Maritime Comm’n,
The defense that the Secretary has not made a determination must be timely and properly raised, since it is nonjurisdictional and waivable. See
Russell
v.
United States,
See,
e.g., Wood
v.
United States,
See,
e.g., Weiner
v.
United States,
To ensure that the regulations are as complete as possible, the Physical Review Council and the Physical Disability Appeal Board are instructed to recommend augmenting provisions to the Secretary whenever they discover that the existing regulations do not provide sufficient guidance. See Army Reg. 15-160 ¶ 3(c).
See,
e.g., Dayley
v.
United States,
See,
e.g., Davis
v.
United States,
See,
e.g., Farrar v. United States,
See,
e.g., Davis
v.
United States,
As already indicated, this would not be such a case.
Physical Evaluation Boards are ad hoc bodies sitting at military installations all over the world. If the court did suspend proceedings to allow a PEB to reconvene, assuming the Board would have the authority to do so In the circumstances, the plaintiff might be faced with travel expenses and undoubtedly would face a “new” PEB; the value of having an administrative body reconsider its prior decision in light of new evidence would be lost. It is probable that most “remanded” cases would have to go to the Correction Board, a permanent body centered in Washington, which may well have had no prior connection with the matter.
One of the arguments advanced by the Government is the possibility of a long interval between a plaintiff’s separation and his trial here. But the staleness of the evidence would be no less of a problem if, as the defendant suggests, we were to suspend proceedings for an administrative decision.
Lite the contract boards, these military tribunals have no subpoena power. In BiancM this defect was outweighed by the indications that Congress desired all evidence to be taken by the boards. Here, where there is no such legislative command, we believe the defect has greater weight.
In addition to the new evidence allowed before the disability appellate boards and the Correction Board, the latter itself reopens cases, not infrequently, which it has previously refused to hear and it often entertains repeated applications for relief (which it denies summarily).
As one example, there might well have been a different development as to The Surgeon General’s advisory opinions. The opportunity to produce rebuttal evidence in court has helped to avert the dangers of such
ex parte
advice. See,
e.g., Hutter
v.
United
States,
