{"schema_version":"0.10.0","id":"LR-2026-0438","record_version":1,"title":"Clinco v. Commissioner: legal hallucinations and evidentiary failures in AI-assisted filing","verification":{"human_verified":false,"method":"automated_gate","auto_verified":true,"score":42.5,"score_breakdown":{"source_authority":12.1,"independent_corroboration":7.0,"implicated_party_confirmed":0.0,"citation_integrity":14.0,"specificity":0.0,"completeness":2.24,"unhedged_language":5.0},"checks":{"schema_valid":true,"every_field_cited":true,"quotes_verbatim":true,"source_fetched":true,"distinct_incident":true,"dates_plausible":true,"sources_agree":true,"source_describes_incident":true,"severe_backed_by_source":true,"record_integrity":true,"eligible":true,"about_this_case":true},"gate_version":"gate-2026-10-18.7","cross_check_model":null,"cross_check_agreement":null,"duplicate_of":null,"verified_by":null,"verified_at":"2026-11-01","extraction_run_id":null,"evidence_level":{"level":"preliminary","reason":"Publisher not yet named · subject to change","original_document":null,"reports_total":1,"reports_independent":0,"reports_derivative":0,"developing":false,"disputed":false,"rules_version":"evidence-2026-10-29.1","computed_at":"2026-11-01","history":[{"date":"2026-11-01","from_level":null,"to_level":"preliminary","reason":"Publisher not yet named · subject to change"}]},"sources_hash":"8f268d35ac95084d38aa2e1b89de64ca10d14ffea6fdcf397550e27f2a0eaaf3"},"system":{"model_name":null,"model_version":null,"developer":"unknown","harness":null,"tools_granted":[],"permissions_scope":null,"autonomy_level":"unknown","guardrails_present":[],"deployment_context":"unknown","tier":null,"lifecycle_stage":null,"integration_type":null,"intended_use":null,"safeguard_state":null,"production_intended":null},"event":{"date_occurred":null,"date_disclosed":"2026-02-09","incident_class":"hallucination","failure_class":null,"agent_involved":null,"secondary_failure_classes":[],"trigger":"unknown","duration":null,"detection_method":"unknown","summary":"In Clinco v. Commissioner, T.C. Memo. 2026-16, the taxpayer disputed IRS income reconstruction and depreciation for a 2015 joint return. Counsel argued that a Notice of Deficiency was invalid for lacking a signature and cited several cases in support. When the Tax Court reviewed the citations, it found that the cases did not exist and that the brief bore marks of AI generation. The court rejected the signature argument on its merits, upheld the deficiencies for unreported income, and disallowed the depreciation deductions. The decision will be entered under Rule 155. The court warned that submitting fictitious caselaw risks sanctions.","tags":[],"date_detected":null,"near_miss":null,"root_cause":null,"root_cause_detail":null,"failure_class_detail":null,"responsible_party":null,"adversarial_actor":null,"input_provenance":null,"time_to_contain":null,"operations_paused":null,"remediation":null,"precursor_events":null,"control_chain":[{"layer":"L3","party":"deployer","party_name":null,"control_id":"I7","outcome":"missing","reason":null,"quote":"The recent Tax Court memorandum opinion in Clinco v. Commissioner, T.C. Memo. 2026-16, serves as a stark warning to tax practitioners regarding two critical areas of practice: the fundamental requirement of substantiating deductions and income, and the emerging ethical peril of utilizing Artificial Intelligence (AI) in legal research without verification.","source_index":0,"reviewed":false}]},"impact":{"direct_loss_usd":null,"remediation_hours":null,"records_exposed":null,"third_parties_affected_count":null,"severity":"minor","harm_class":[],"affected_description":null,"protected_class_involved":null,"data_categories_exposed":[],"loss_range_usd":null,"reversibility":null,"downstream_exposure_count":null},"evidence":{"sources":[{"url":"https://www.currentfederaltaxdevelopments.com/blog/2026/2/9/legal-hallucinations-and-evidentiary-failures-a-review-of-clinco-v-commissioner","publisher":"Current Federal Tax Developments","date":"2026-02-09","type":"press","title":"Legal Hallucinations and Evidentiary Failures: A Review of Clinco v. Commissioner - Current Federal Tax Developments","archived_url":null,"attachment":"first_report"}],"per_field_confidence":{"event.incident_class":"C","context.industry":"C","impact.severity":"D","event.control_chain":"C","event.summary":"C","system.autonomy_level":"D","system.deployment_context":"D","event.trigger":"D","event.detection_method":"D","context.country":"D","system.developer":"D","event.date_disclosed":"D","context.denominator_available":"D"},"field_citations":{"event.incident_class":[{"source_index":0,"quote":"Judge Holmes’s opinion not only addresses standard unreported income and depreciation issues but also delivers a blistering critique of a brief containing fictitious case citations likely generated by an AI model."}],"context.industry":[{"source_index":0,"quote":"The recent Tax Court memorandum opinion in Clinco v. Commissioner, T.C. Memo. 2026-16, serves as a stark warning to tax practitioners regarding two critical areas of practice: the fundamental requirement of substantiating deductions and income, and the emerging ethical peril of utilizing Artificial Intelligence (AI) in legal research without verification."}],"impact.severity":[{"source_index":0,"quote":"The Court’s analysis of these citations revealed a disturbing reality: the cases did not exist."}],"event.control_chain":[{"source_index":0,"quote":"The recent Tax Court memorandum opinion in Clinco v. Commissioner, T.C. Memo. 2026-16, serves as a stark warning to tax practitioners regarding two critical areas of practice: the fundamental requirement of substantiating deductions and income, and the emerging ethical peril of utilizing Artificial Intelligence (AI) in legal research without verification."}],"event.summary":[{"source_index":0,"quote":"The case concerned the 2015 joint return of the late Peter Clinco, an attorney and entrepreneur, and his wife."},{"source_index":0,"quote":"To support this position, counsel cited several cases: Cacchillo v. Commissioner, Miller v. Commissioner, and Tefel v. Commissioner."},{"source_index":0,"quote":"The Court’s analysis of these citations revealed a disturbing reality: the cases did not exist."},{"source_index":0,"quote":"The bouillabaisse of case names, reporter citations, and legal propositions suggests something cooked up by AI."},{"source_index":0,"quote":"The Tax Court upheld the deficiencies regarding the unreported income and disallowed depreciation, resulting in a decision to be entered under Rule 155."},{"source_index":0,"quote":"Submitting a brief with fictitious caselaw is a recipe for sanctions."}]},"notes_on_gaps":"The sources do not name the AI model, its developer, harness, tools, or deployment setting, so no system fields are given. The sources say the citations were likely AI-generated but do not state that an autonomous agent was involved, so agent fields and failure_class are omitted. No date of occurrence, opinion date, or disclosure date beyond the press article date is stated; the 2026-02-09 date is the press article's date. Detection is not stated as a method, and the root cause and responsible party are not stated. No sanction is stated for this case. Country is not stated and was not filled. Judgements made: severity set to minor because the sources show the fictitious citations were confined to one brief in one case with no third party affected; the I7 grounding-control 'missing' outcome is inferred from the source's statement about the peril of using AI without verification; the risk RK14 reflects the reliance on false citations. The source is a secondary press review, prepared with assistance from NotebookLM, not the court opinion itself. No remediations are stated. [case created by the backfill: read by claude-haiku-5-5, backfill-2026-11-01.2, 2026-11-01; not yet reviewed] [2026-11-01: evidence level set: Preliminary (Publisher not yet named · subject to change)]"},"context":{"industry":"legal services","org_size_band":null,"country":"unknown","denominator_available":false,"denominator":null,"related_incident_ids":[],"systemic_exposure":null,"shared_model_id":null,"upstream_incident_id":null,"incident_evidence":null,"regulatory":null,"coverage":null},"narrative":{"steps":[{"step":"went_wrong","text":"The cited cases did not exist.","quote":"The Court’s analysis of these citations revealed a disturbing reality: the cases did not exist.","source_index":0,"grade":"C"}],"model":"claude-haiku-5-5","prompt_version":"backfill-2026-11-01.2","extracted_at":"2026-11-01","source_urls":["https://www.currentfederaltaxdevelopments.com/blog/2026/2/9/legal-hallucinations-and-evidentiary-failures-a-review-of-clinco-v-commissioner"]},"analysis":{"sections":{"timeline":[{"text":"The 2015 joint return at issue was filed.","quote":"The case concerned the 2015 joint return of the late Peter Clinco, an attorney and entrepreneur, and his wife.","source_index":0,"when":"2015"},{"text":"Two properties were placed in service.","quote":"The final issue concerned $56,798 in depreciation deductions claimed on Schedule E for two properties placed in service in May 2015.","source_index":0,"when":"2015-05"},{"text":"The Court analysed the citations and found the cases did not exist.","quote":"The Court’s analysis of these citations revealed a disturbing reality: the cases did not exist.","source_index":0,"when":null}]},"model":"claude-haiku-5-5","prompt_version":"backfill-2026-11-01.2","extracted_at":"2026-11-01","source_urls":["https://www.currentfederaltaxdevelopments.com/blog/2026/2/9/legal-hallucinations-and-evidentiary-failures-a-review-of-clinco-v-commissioner"]}}