Facts

Parties and instances: The appellant is the DI office of the Canton of Zurich; the respondent is [A.] , represented by attorney Thomas Laube. The lower instance is the Social Insurance Court of the Canton of Zurich (decision of 18 May 2020, IV.2018.00634). The I. Social Law Division of the Federal Supreme Court is competent (judgment 8C_487/2020 of 3 November 2020).

Subject matter: Disability insurance, disability pension, re-registration.

Facts:

  • The respondent, born in 1979, applied for benefits from disability insurance in April 2014. By decision of 13 July 2015, the DI office denied any entitlement to benefits; the decision was not challenged and became final.
  • A new application was filed in June 2016. Based on a bidisciplinary expert opinion (Dr. med. [B.] , rheumatology, and Prof. Dr. med. [C.] , psychiatry, of 2 November 2020), the DI office again rejected the benefits application by decision of 29 June 2018.
  • The Social Insurance Court upheld the appeal, annulled the decision of 29 June 2018, awarded a full disability pension from 1 December 2016, and imposed the costs of the court-ordered expert opinion on the DI office. It relied on the court-ordered expert opinion of med. pract. [D.] (specialist in psychiatry and psychotherapy) of 5 September 2019.
  • It is undisputed that the respondent suffers from no somatic complaints restricting her work capacity.

Requests: The DI office requests that the lower court's decision be set aside and the decision of 29 June 2018 be confirmed, and also requests that suspensive effect be granted. The respondent requests non-entry into the appeal, alternatively dismissal. The INO waived its statement. By order of 7 October 2020, the Federal Supreme Court granted suspensive effect.

Legal question: Whether the lower court rightly awarded a full disability pension from 1 December 2016, and whether the court-ordered expert opinion of 5 September 2019 is a reliable basis for the evidence.

Considerations

Admissibility: The appeal concerns a public-law matter (Art. 82 lit. a FSCA) against a final decision (Art. 90 FSCA) of a last cantonal instance (Art. 86 para. 1 lit. d FSCA). The DI office has standing to appeal (Art. 89 para. 2 lit. d FSCA in conjunction with Art. 62 para. 1bis GSSLA and Art. 41 para. 1 lit. i InvIO; BGE 138 V 339). The time limit was observed (Art. 100 para. 1, Art. 44 para. 1, Art. 46 para. 1 lit. b FSCA). The appeal is admissible.

Scope of review: The Federal Supreme Court applies the law of its own motion (Art. 106 para. 1 FSCA) and is bound by the lower court's findings of fact unless they are manifestly incorrect or based on a violation of law (Art. 105 paras. 1 and 2, Art. 97 para. 1 FSCA). The specific assessment of evidence is reviewed only for arbitrariness; the strict principle of complaint applies (BGE 140 V 50 consid. 4.2).

Legal framework: The lower court correctly set out the relevant provisions on disability (Art. 8 para. 1 GSSLA), inability to earn income (Art. 7 GSSLA), psychological illnesses (BGE 143 V 418; 141 V 281), entitlement to a pension (Art. 28 InvIA), as well as re-registration (Art. 87 para. 3 InvIO; BGE 141 V 585) and revision (Art. 17 para. 1 GSSLA). In relation to court-ordered expert opinions, the judge may not deviate without compelling reasons; such reasons exist where expert opinions are contradictory or where a convincing superior expert opinion is available (BGE 125 V 351 consid. 3b/aa).

Change in actual circumstances and arbitrariness: After the final denial of 13 July 2015, a change in the degree of disability relevant to the pension (Art. 17 GSSLA) had to have occurred by 29 June 2018. The lower court relied on a 'crescendo' of complaints, which is in irreconcilable contradiction with the expert, who found no relevant change. Moreover, the lower court made impermissible findings concerning a period before the final decision and in effect carried out a reconsideration under Art. 53 para. 2 GSSLA, although this power belongs only to the insurance carrier. The assessment of evidence is therefore contradictory and arbitrary.

Defects of the court-ordered expert opinion: The DI office's legal representatives rightly complained that the expert made the legal assessment and conducted what amounted to an assessment of evidence, which diminishes the probative value (SVR 2016 UV No. 27; BGE 140…