The plaintiff, a cafeteria worker in the Worcester school department, appealed the denial of her claim for accidental disability retirement benefits through the prescribed channels of the local board, the Contributory Retirement Appeal Board (CRAB), and the Superior Court.2 We hold that CRAB erred as matter of law in ruling that the plaintiff had failed to receive majority approval by a regional medical panel where the certificates of only two members were considered by CRAB and those two members disagreed.

*729The injury in question occurred in 1981 when the plaintiff lifted a heavy mixing bowl out of a deep sink while at work. She received treatment for back pain and also received workers’ compensation payments. In connection with her workers’ compensation claim, she was examined and evaluated on several occasions. She never returned to work and remained on workers’ compensation until 1991, when her benefits expired.

The plaintiff initially applied for accidental disability retirement benefits in March, 1983, and apparently requested that consideration of her application be deferred while she was receiving workers’ compensation benefits. The application was accepted on February 20, 1992. Her claim first was denied by the Worcester retirement board, but was resubmitted for examination by a new medical panel in November, 1993. The new medical panel consisted of Drs. Carver, Metzmaker, and Duff who evaluated the plaintiff on January 25, February 2, and February 4, 1994, respectively.3 Dr. Carver certified that the plaintiff was disabled and that her disability was permanent, but that the disability was not such as might have been the natural and proximate result of the September 9, 1981, incident. Dr. Metzmaker certified that the plaintiff was disabled, that her disability was permanent, and that there was a causal connection between the disability and the sink incident. Dr. Duff certified that the plaintiff was not disabled. The local board again denied her claim, and her appeal to CRAB followed.

The administrative law judge (ALJ) to whom the case was referred for hearing under G. L. c. 32, § 16(4), ruled that “Dr. Duff’s evaluation was not in accordance with []G. L. c. 32, [§] 6(3) and applicable retirement case law. As such his findings are invalid. . . . Both the circumstances of his examination and Dr. Duff’s narrative report reflect a disbelieving, somewhat judgemental [szc] attitude toward the Appellant which creates *730the appearance of bias or lack of objectivity.” It is clear that the ALJ, and subsequently CRAB, regarded Dr. Duff’s opinion as a nullity4 *— as if it had not been filed — and not merely as a report that was to be considered but was not credible or persuasive.

When a negative certificate of a medical panel member is deficient because an incorrect legal standard has been applied by a physician,5 CRAB may consider all the evidence, including the certificate, and conclude that the applicant has satisfied her burden on the question addressed by the legally flawed certificate. Kelley v. Contributory Retirement Appeal Bd., 341 Mass. 611, 617 (1961), construing Quincy Retirement Bd. v. Contributory Retirement Appeal Bd., 340 Mass. 56, 61-62 (1959). An applicant has a right to try to persuade CRAB that the applicant should prevail on the whole record. Ibid. But when CRAB is not persuaded on the whole record in favor of the claimant where there is a defective negative certificate, CRAB cannot then deny the claim without providing an opportunity for the applicant to supply a certificate that is valid.6 Ibid. When a certificate is invalidated by CRAB on the ground that it was not supplied by a neutral and fair assessment from an unbiased physician, the principles of the Kelley and Quincy cases should apply. Specifically, the applicant must be given an opportunity to remedy the problem caused by the deficient certificate by trying to persuade CRAB in her favor on the balance of the record; if CRAB is not persuaded, the applicant must then be given an opportunity to supply a certificate that is valid.

*731Here, the plaintiff was not given the opportunity to supply an additional valid certificate. Instead, CRAB disposed of the appeal on the mechanical ground that a “majority” of the medical panel did not affirmatively certify the claim. If CRAB regarded the medical panel as composed of the original three physicians, this ruling was inconsistent with its ruling that Dr. Duff’s certificate was a nullity that could not be considered. In effect, CRAB gave the nullified certificate the legitimacy of a negative certificate and thereby considered it in spite of ruling that it would not.

On the other hand, if CRAB viewed the panel as consisting of only two physicians, it is mathematically correct to observe that one vote is not a majority of a panel of two, but the observation is something of a sophistry in this context. The statute requires that a majority of the medical panel certify incapacity affirmatively, G. L. c. 32, § 6(1), and that the panel be composed of three physicians, G. L. c. 32, § 6(3)(o). If one panel member is disqualified, two affirmative votes are sufficient, as discussed above. But if the two surviving votes are split, the plaintiff cannot be deprived of her right to the consideration of a third neutral panel member by the simple observation that one is not a majority of two.

The defendant suggests that the evidence before CRAB was ample to permit it to reject the claim. The ALJ and CRAB, however, found the mathematical approach to be definitive.7 In any event, CRAB was not entitled to deny the claim on a review of the substance of the remaining medical evidence. The plaintiff has a statutory right to obtain a third opinion that might be favorable to her claim and to submit that opinion to the local board for it to render a decision that could then be reviewed by CRAB.

The appropriate remedy is a remand directing CRAB to submit the matter to a new regional medical panel. Sufficient time has passed to make the original panel’s work outdated, and there is, of course, no way for a new third member to examine *732the same physical facts as were previously examined.8 All three members of the new panel must examine the plaintiff.

The Superior Court judgment is vacated, and a new judgment shall enter remanding the case to CRAB for further proceedings in conformance with this opinion.

So ordered.