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       "value": "The independent quantitative evaluation, and the reason the entry does not simply repeat advocacy figures. Chicago sample: 85,572 incidents, 6 February 2017 to the end of 2019. Note for anyone reusing it: the frequently quoted procedural gains — alerts arriving 93 seconds before 911 calls, locations about 300 feet closer — are the KANSAS CITY results in this study and are not Chicago findings.",
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       "value": "Litigation-side research, published three months before the OIG audit and reaching a similar shape from different data: 1 July 2019 to 14 April 2021, 89% of deployments turned up no gun-related crime and 86% no crime report at all. Labelled here as advocacy research, not an audit — the entry's headline figure is the OIG's, not this one.",
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      "title": "SoundThinking — the vendor's rebuttals to the OIG audit and to the MacArthur Justice Center report",
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       "value": "The other side, kept in deliberately. SoundThinking argues the OIG measured the wrong thing (dispositions of police responses rather than detection accuracy) and published a separate point-by-point response to the MJC study at soundthinking.com/blog/soundthinkings-response-to-the-macarthur-justice-center-report/, plus a commissioned Edgeworth Economics critique of its methodology. The company also renamed itself from ShotSpotter, Inc. on 10 April 2023; the product kept the old name.",
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      "title": "ABC7 Chicago — Chicago ShotSpotter contract ends Sunday, city to begin dismantling technology Monday (22 Sep 2024)",
      "url": "https://abc7chicago.com/post/chicago-shotspotter-contract-ends-sunday-city-begin-dismantling-gunshot-detection-technology-monday/15341343/",
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       "value": "The end, with the city's own wording: 'Effective Monday, September 23, 2024, at 12:01 am, the Chicago Police Department will no longer be utilizing ShotSpotter technology', followed by a 60-day decommissioning. Mayor Johnson's stated reason: 'The ultimate goal is to deploy resources on the most effective strategies and tactics proven to accelerate the current downward trend in violent crime. We have to explore better options that save more lives.' The city's own statement page (chicago.gov, February 2024) carries the same text but returns 403 to automated fetching.",
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      "title": "WTTW — City Council Votes 33-14 to Again Rebuke Mayor Brandon Johnson's Decision to Scrap ShotSpotter (18 Sep 2024)",
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       "value": "The fight over the ending, which is not settled. The council voted 33-14 to hand contracting authority to Superintendent Larry Snelling, who supports the technology; Johnson called the ordinance illegal, Snelling did not sign over the objection of the mayor who appointed him, and the system went dark four days later.",
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      "title": "Chicago Sun-Times — City Council members want Johnson to tackle replacing ShotSpotter (12 May 2026)",
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       "value": "Currency check, and the reason this entry says nothing has replaced it. Twenty months after shutdown: 15 firms answered an RFI, 9 answered the RFP including SoundThinking, $13.9M sits in two budgets, no contract is awarded. Chief Procurement Officer Sharla Roberts: 'An RFP of this size, complexity and nature takes 18 to 24 months and sometimes longer to award.' A resolution filed 5 May 2026 with 35 council signatures accuses the mayor of obstruction; hearing set for 3 June 2026. A free six-month muzzle-flash pilot from Shooter Detection Systems was offered in the 9th District in January 2025; no source confirms it went live.",
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      "title": "Chicago Sun-Times — Chicago settles ShotSpotter lawsuit, considers bringing gunshot-detection system back (15 Aug 2025)",
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       "value": "The legal counterpart to the OIG's finding that the technology changed police behaviour: Chicago paid $90,000 to settle a 2022 federal suit by Daniel Ortiz and Derick Scruggs and conceded that a ShotSpotter alert alone does not justify stopping or frisking someone near the alert. Separately, the city agreed in March 2026 to pay $500,000 to Michael Williams, charged with murder in 2020 largely on an alert and held nearly a year before prosecutors dropped the case in July 2021 for lack of evidence.",
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      "title": "WTTW — Steep Drop in Homicides Continued for Full Year After ShotSpotter Was Removed: Analysis (29 Dec 2025)",
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       "value": "What happened after, reported here as correlation and nothing more. Police beats that had had sensors saw roughly a 32% fall in homicides between 1 January and 22 September 2025, but homicides fell about 30% citywide in 2025 to a 60-year low, including where sensors never existed. A University of Chicago analysis reported on 27 May 2026 found faster responses to top-priority 911 calls in former ShotSpotter beats, but it excluded gunfire calls from the data — a limitation critics reasonably press. Both WTTW pages return 403 to automated fetching; figures here come from search-result text and should be re-read before any figure is added to the entry body.",
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      "supportNote": "The Inspector General's report gives the numerator and the extent: \"network coverage in 12 police Districts over 100 square miles\". It nowhere states how many police districts Chicago has; the city's own Community Commission page supplies that: the ordinance created \"a citywide Community Commission and 22 elected District Councils, one in each police district\".",
      "caveat": "The report documents the twelve covered districts by number. It does not state how many police districts Chicago has in total, so the denominator of twenty-two rests on the city's police-district structure rather than on this report.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-94ca4a36d8e328e9",
      "field": "snippet",
      "text": "more than 100 square miles of the South and West Sides",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-7fc294f6449adc69",
       "src-512cb0d291ba200a"
      ],
      "supportNote": "The Inspector General carries the extent verbatim — \"over 100 square miles\" — but never describes where the coverage lies. South Side Weekly does, from city records: the contract \"requires ShotSpotter to monitor twelve police districts on the South and West Sides\".",
      "caveat": "South Side Weekly adds the one qualification to a pure South-and-West framing: the vendor also monitored the area around Kennedy Expressway billboards on the Northwest Side, at no charge.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-ba53ccdbd9c99952",
      "field": "snippet",
      "text": "The city's Inspector General found in 2021 that 9.1% of police responses to alerts turned up evidence of a gun crime",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f9592ff4f373e5c1",
       "src-7fc294f6449adc69"
      ],
      "supportNote": "The Office of Inspector General published this finding on 24 August 2021: \"A total of 4,556 of those 41,830 dispositions indicate that evidence of a gun-related criminal offense was found, representing 9.1% of CPD responses to ShotSpotter alerts.\" The figure counts what police recorded after responding; it is not a measure of whether the sensors correctly detected gunfire.",
      "caveat": "The figure measures what police documented after responding, not whether a gunshot occurred. The vendor makes exactly this objection, arguing the audit examined the police response rather than the detection.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-501a681c001dd095",
      "field": "snippet",
      "text": "Mayor Brandon Johnson let the contract lapse",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-479b9a00a9a0d488",
       "src-b38a7b4c822f7d07"
      ],
      "supportNote": "WTTW reports the City Council voting 33-14 on 18 September 2024 \"to again endorse an effort to overturn Mayor Brandon Johnson's decision to scrap the city's gunshot detection system, ShotSpotter, which is set to be turned off Sunday,\" and the ordinance sought to move the decision out of the mayor's hands; ABC7 reports that the contract then ended without renewal. WTTW blocks automated retrieval, so its wording was confirmed through search results rather than by opening the page.",
      "caveat": "The ending was contested rather than quiet. The City Council voted twice to reverse the decision and moved to hand the choice to the police superintendent; the system went dark anyway.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-b123ef6c84bc8643",
      "field": "snippet",
      "text": "CPD stopped using the system on 23 September 2024",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-b38a7b4c822f7d07"
      ],
      "supportNote": "ABC7 quotes the city's own notice: \"Effective Monday, September 23, 2024, at 12:01 am, the Chicago Police Department will no longer be utilizing ShotSpotter technology.\"",
      "caveat": null,
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-1206712bac494b17",
      "field": "snippet",
      "text": "No replacement has been procured since.",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
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      ],
      "supportNote": "Twenty months after the shutdown the Sun-Times reports that no contract has been awarded: \"Nothing has happened since then — even though the last two city budgets set aside a combined $13.9 million for the replacement technology.\" Fifteen firms answered the request for information and nine answered the request for proposals; Chief Procurement Officer Sharla Roberts said \"An RFP of this size, complexity and nature takes 18 to 24 months and sometimes longer to award.\"",
      "caveat": "A procurement is under way rather than abandoned: nine firms have bid and money is budgeted. What has not happened is an award.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
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     },
     {
      "id": "clm-8760bdfe792063bf",
      "field": "impact",
      "text": "The Chicago Office of Inspector General reviewed every alert confirmed as a probable gunshot and dispatched between 1 January 2020 and 31 May 2021: of those 50,176 alerts, 41,830 recorded a disposition, and 4,556 of those found evidence of a gun-related offence — 9.1% of police responses.",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f9592ff4f373e5c1",
       "src-7fc294f6449adc69"
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      "supportNote": "The OIG analysed \"all ShotSpotter alert notifications that occurred between January 1, 2020, and May 31, 2021\" and reported: \"Of the 50,176 confirmed and dispatched ShotSpotter alerts, 41,830 report a disposition — the outcome of the police response to an incident. A total of 4,556 of those 41,830 dispositions indicate that evidence of a gun-related criminal offense was found, representing 9.1% of CPD responses to ShotSpotter alerts.\" The remaining 8,346 alerts (16.6%) carried no disposition code at all.",
      "caveat": "The 9.1% is calculated against all 50,176 responses, not against the 41,830 that recorded an outcome. For 8,346 alerts no outcome was recorded at all, which the audit treats as a gap in police record-keeping rather than as a finding about the alerts.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-818faf4c0622cc58",
      "field": "impact",
      "text": "A documented investigatory stop followed 2.1%.",
      "statementKind": "quantitative",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-f9592ff4f373e5c1",
       "src-7fc294f6449adc69"
      ],
      "supportNote": "The OIG found 1,056 alerts sharing an event number with an investigatory stop report: \"at least one investigatory stop is documented under a matching event number in 2.1% of all CPD responses to ShotSpotter alerts.\" A separate keyword search turned up a further 1,366 stop reports mentioning ShotSpotter whose event numbers matched no alert.",
      "caveat": "The audit says this figure may understate what happened: stops recorded without a matching event number would not appear, and the OIG concluded that police record-keeping was obstructing a meaningful analysis.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
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     },
     {
      "id": "clm-f9aa43c4c940d069",
      "field": "impact",
      "text": "A synthetic-control evaluation of Chicago and Kansas City funded by the National Institute of Justice found that the software detected gunfire as advertised",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
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       "src-9b9f7c3c262b943a"
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      "supportNote": "The National Institute of Justice published the evaluation (award 2019-R2-CX-0004, Piza et al., 1 January 2023), whose Chicago sample is 85,572 gunfire incidents detected between 6 February 2017 and 31 December 2019. Its lead author summarised the detection result as: \"All of that I take to communicate that the software does what the vendor promises.\"",
      "caveat": null,
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-f7a4f9982738ec75",
      "field": "impact",
      "text": "gun violence did not fall in either city after ShotSpotter arrived and shootings were no more likely to be solved",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
      "mappingStatus": "mapped",
      "sourceRefs": [
       "src-9b9f7c3c262b943a",
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      "supportNote": "The evaluation's lead author, Eric Piza, states it plainly: \"Gun violence did not reduce in either (Kansas City or Chicago) following the introduction of ShotSpotter, and shootings were not anymore likely to be solved in either city following the introduction of ShotSpotter.\"",
      "caveat": "The frequently quoted procedural gains from the same study — alerts arriving 93 seconds before 911 calls and locating shootings some 300 feet closer — are the Kansas City results, not Chicago's.",
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
      }
     },
     {
      "id": "clm-299cb56d5f5f530a",
      "field": "lesson",
      "text": "Accuracy was never the question Chicago could not answer.",
      "statementKind": "descriptive",
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      "mappingStatus": "mapped",
      "sourceRefs": [
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      "supportNote": "Both sides of the argument agree on this point. The evaluation's lead author says \"the software does what the vendor promises,\" and the vendor's own rebuttal insists the audit was aimed elsewhere: \"it was an audit of CPD's use of the tool, not the efficacy of the tool itself.\"",
      "caveat": null,
      "interpretation": {
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     },
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      "field": "lesson",
      "text": "The city could hear the shots",
      "statementKind": "descriptive",
      "textMode": "verbatim-from-project-record",
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      "sourceRefs": [
       "src-9b9f7c3c262b943a",
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      "supportNote": "The independent evaluation found the detection worked: its Chicago component logged 85,572 detected gunfire incidents, and its lead author concluded that \"the software does what the vendor promises.\"",
      "caveat": null,
      "interpretation": {
       "added": false,
       "interpolation": false,
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      }
     },
     {
      "id": "clm-268e2543fef0fd47",
      "field": "lesson",
      "text": "what its own watchdog could not find was what the police response produced.",
      "statementKind": "descriptive",
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      "sourceRefs": [
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      "supportNote": "The city's Inspector General set out to describe the outcomes of police responses and found it could not: 8,346 of the 50,176 alerts carried no disposition code at all, and the report concludes that if the low stop figure is \"attributable in part to missing or non-matched records of investigatory stops... CPD's record-keeping practices are obstructing a meaningful analysis of the effectiveness of the technology.\"",
      "caveat": null,
      "interpretation": {
       "added": false,
       "interpolation": false,
       "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion."
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    "sources": [
     {
      "id": "src-f9592ff4f373e5c1",
      "title": "Chicago Office of Inspector General — The Chicago Police Department's Use of ShotSpotter Technology (24 Aug 2021)",
      "url": "https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-alerts-rarely-lead-to-evidence-of-a-gun-related-crime-and-that-presence-of-the-technology-changes-police-behavior/",
      "publisher": {
       "name": null,
       "domain": "igchicago.org",
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       "publishedAt": "2021-08-24",
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       "type": "descriptive-source-note",
       "value": "The load-bearing document. Verbatim: 'A total of 50,176 ShotSpotter alerts were confirmed as probable gunshots'; 'a total of 4,556 indicate that evidence of a gun-related criminal offense was found, representing 9.1% of CPD responses'; 'at least one investigatory stop is documented under a matching event number in 2.1% of all CPD responses.' Also dates the contract: '$33 million, three-year contract with ShotSpotter began on August 20, 2018', extended in December 2020 to 19 August 2023. The OIG states its own data were incomplete and irreconcilable. Caution for a future check: the report PDF did not yield machine-readable text in this review, so these figures are quoted from the OIG's release page rather than the PDF body.",
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      },
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       "archiveUrl": "https://web.archive.org/web/20260628172322/https://igchicago.org/2021/08/24/oig-finds-that-shotspotter-alerts-rarely-lead-to-evidence-of-a-gun-related-crime-and-that-presence-of-the-technology-changes-police-behavior/",
       "archivedAt": "2026-06-28",
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     {
      "id": "src-7fc294f6449adc69",
      "title": "Chicago Office of Inspector General — full report PDF (August 2021)",
      "url": "https://igchicago.org/wp-content/uploads/2021/08/Chicago-Police-Departments-Use-of-ShotSpotter-Technology.pdf",
      "publisher": {
       "name": null,
       "domain": "igchicago.org",
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      "locator": {
       "type": "descriptive-source-note",
       "value": "The report itself, for readers who want the methodology. It issues none of the recommendations an audit usually carries and says so: OIG describes the document as a descriptive analysis published to inform the public. 985 KB.",
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      },
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     },
     {
      "id": "src-e94b7add9160654d",
      "title": "National Institute of Justice — Piza et al., The Impact of Gunshot Detection Technology on Gun Violence in Kansas City and Chicago: A Multi-Pronged Synthetic Control Evaluation",
      "url": "https://nij.ojp.gov/library/publications/impact-gunshot-detection-technology-gun-violence-kansas-city-and-chicago-multi",
      "publisher": {
       "name": null,
       "domain": "nij.ojp.gov",
       "classification": "not-classified"
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      "temporal": {
       "publishedAt": "2023-01-01",
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       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The independent quantitative evaluation, and the reason the entry does not simply repeat advocacy figures. Chicago sample: 85,572 incidents, 6 February 2017 to the end of 2019. Note for anyone reusing it: the frequently quoted procedural gains — alerts arriving 93 seconds before 911 calls, locations about 300 feet closer — are the KANSAS CITY results in this study and are not Chicago findings.",
       "exact": false
      },
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     },
     {
      "id": "src-9b9f7c3c262b943a",
      "title": "Northeastern University — ShotSpotter improves detection and response to gunfire, but doesn't reduce crime (23 May 2024)",
      "url": "https://news.northeastern.edu/2024/05/23/shotspotter-gunfire-detection-response/",
      "publisher": {
       "name": null,
       "domain": "news.northeastern.edu",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
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       "publishedAt": "2024-05-23",
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       "retrievedAt": null,
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      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Plain-language account of the same evaluation by its lead author, Eric Piza. Carrying sentence: 'Gun violence did not reduce in either (Kansas City or Chicago) following the introduction of ShotSpotter, and shootings were not anymore likely to be solved in either city.' Piza's own site states the project also produced peer-reviewed journal articles; those were not individually verified here, which is why this entry is graded independent rather than peer-reviewed.",
       "exact": false
      },
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     {
      "id": "src-7db747a75d032fca",
      "title": "MacArthur Justice Center (Northwestern Pritzker School of Law) — ShotSpotter Generated Over 40,000 Dead-End Police Deployments in Chicago in 21 Months (May 2021)",
      "url": "https://www.macarthurjustice.org/shotspotter-generated-over-40000-dead-end-police-deployments-in-chicago-in-21-months-according-to-new-study/",
      "publisher": {
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       "domain": "macarthurjustice.org",
       "classification": "not-classified"
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      "language": "und",
      "role": "background",
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      "temporal": {
       "publishedAt": "2021-05-03",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-23",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "Litigation-side research, published three months before the OIG audit and reaching a similar shape from different data: 1 July 2019 to 14 April 2021, 89% of deployments turned up no gun-related crime and 86% no crime report at all. Labelled here as advocacy research, not an audit — the entry's headline figure is the OIG's, not this one.",
       "exact": false
      },
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     {
      "id": "src-8ba47d02a55337b7",
      "title": "SoundThinking — the vendor's rebuttals to the OIG audit and to the MacArthur Justice Center report",
      "url": "https://www.soundthinking.com/blog/soundthinkings-commentary-on-chicago-oig-report/",
      "publisher": {
       "name": null,
       "domain": "soundthinking.com",
       "classification": "not-classified"
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      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
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      "temporal": {
       "publishedAt": "2024-05-20",
       "updatedAt": null,
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-23",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The other side, kept in deliberately. SoundThinking argues the OIG measured the wrong thing (dispositions of police responses rather than detection accuracy) and published a separate point-by-point response to the MJC study at soundthinking.com/blog/soundthinkings-response-to-the-macarthur-justice-center-report/, plus a commissioned Edgeworth Economics critique of its methodology. The company also renamed itself from ShotSpotter, Inc. on 10 April 2023; the product kept the old name.",
       "exact": false
      },
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     },
     {
      "id": "src-b38a7b4c822f7d07",
      "title": "ABC7 Chicago — Chicago ShotSpotter contract ends Sunday, city to begin dismantling technology Monday (22 Sep 2024)",
      "url": "https://abc7chicago.com/post/chicago-shotspotter-contract-ends-sunday-city-begin-dismantling-gunshot-detection-technology-monday/15341343/",
      "publisher": {
       "name": null,
       "domain": "abc7chicago.com",
       "classification": "not-classified"
      },
      "sourceType": "web-page",
      "language": "und",
      "role": "claim-evidence",
      "claimRefs": [
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      "temporal": {
       "publishedAt": "2024-09-22",
       "updatedAt": "2024-09-23",
       "sourceCheckedAt": null,
       "recordLastVerifiedAt": "2026-07-26",
       "dossierCreatedAt": "2026-08-23",
       "retrievedAt": null,
       "status": "publication-and-record-dates-recorded"
      },
      "locator": {
       "type": "descriptive-source-note",
       "value": "The end, with the city's own wording: 'Effective Monday, September 23, 2024, at 12:01 am, the Chicago Police Department will no longer be utilizing ShotSpotter technology', followed by a 60-day decommissioning. Mayor Johnson's stated reason: 'The ultimate goal is to deploy resources on the most effective strategies and tactics proven to accelerate the current downward trend in violent crime. We have to explore better options that save more lives.' The city's own statement page (chicago.gov, February 2024) carries the same text but returns 403 to automated fetching.",
       "exact": false
      },
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     },
     {
      "id": "src-479b9a00a9a0d488",
      "title": "WTTW — City Council Votes 33-14 to Again Rebuke Mayor Brandon Johnson's Decision to Scrap ShotSpotter (18 Sep 2024)",
      "url": "https://news.wttw.com/2024/09/18/city-council-votes-33-14-again-rebuke-mayor-brandon-johnson-s-decision-scrap-shotspotter",
      "publisher": {
       "name": null,
       "domain": "news.wttw.com",
       "classification": "not-classified"
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      "language": "und",
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       "value": "Currency check, and the reason this entry says nothing has replaced it. Twenty months after shutdown: 15 firms answered an RFI, 9 answered the RFP including SoundThinking, $13.9M sits in two budgets, no contract is awarded. Chief Procurement Officer Sharla Roberts: 'An RFP of this size, complexity and nature takes 18 to 24 months and sometimes longer to award.' A resolution filed 5 May 2026 with 35 council signatures accuses the mayor of obstruction; hearing set for 3 June 2026. A free six-month muzzle-flash pilot from Shooter Detection Systems was offered in the 9th District in January 2025; no source confirms it went live.",
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       "value": "The legal counterpart to the OIG's finding that the technology changed police behaviour: Chicago paid $90,000 to settle a 2022 federal suit by Daniel Ortiz and Derick Scruggs and conceded that a ShotSpotter alert alone does not justify stopping or frisking someone near the alert. Separately, the city agreed in March 2026 to pay $500,000 to Michael Williams, charged with murder in 2020 largely on an alert and held nearly a year before prosecutors dropped the case in July 2021 for lack of evidence.",
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       "value": "What happened after, reported here as correlation and nothing more. Police beats that had had sensors saw roughly a 32% fall in homicides between 1 January and 22 September 2025, but homicides fell about 30% citywide in 2025 to a 60-year low, including where sensors never existed. A University of Chicago analysis reported on 27 May 2026 found faster responses to top-priority 911 calls in former ShotSpotter beats, but it excluded gunfire calls from the data — a limitation critics reasonably press. Both WTTW pages return 403 to automated fetching; figures here come from search-result text and should be re-read before any figure is added to the entry body.",
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      "title": "South Side Weekly — Which Wards Have ShotSpotter?",
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       "value": "Ward-level mapping of the sensor network from city records, and the source for the South and West Sides framing: the contract \"requires ShotSpotter to monitor twelve police districts on the South and West Sides\". It also names the one qualification — free monitoring around Kennedy Expressway billboards on the Northwest Side.",
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