{ "schemaVersion": "1.0.0", "constitutionVersion": "1.0.0", "createdAt": "2026-08-12T00:00:00Z", "description": "Append-only Evidence Passport records. Old revisions are immutable; corrections create a new revision and preserve the previous permalink.", "entity": { "type": "project", "id": "london-low-traffic-neighbourhoods", "title": "Low Traffic Neighbourhoods (LTNs)", "canonicalUrl": "https://1001smartcities.org/projects/london-low-traffic-neighbourhoods/" }, "currentRevisionId": "2026-08-26-claim-mapping", "revisions": [ { "id": "2026-08-20-source-dates", "createdAt": "2026-08-20T19:29:52Z", "effectiveAt": "2026-07-25", "changeType": "baseline", "summary": "Created the first structured Evidence Passport with 1 claim and 4 source dossiers.", "preparedBy": { "type": "automation", "label": "AI-assisted evidence preparation", "humanApproved": false }, "review": { "status": "unreviewed", "by": null, "date": null, "note": "Awaiting operator and domain-expert review; publication of this revision implies neither." }, "changes": [ { "operation": "add", "path": "/evidencePassport", "summary": "Added claim-level evidence mapping and source dossiers." }, { "operation": "add", "path": "/revisionHistory", "summary": "Established a permanent, hash-addressed baseline revision." } ], "snapshotHash": "sha256:d3168842c91fdcbd6b6b898d73a04ca91610efed3ea3ddc7b01abf7a039d2cba", "snapshot": { "asOf": "2026-07-25", "projectFingerprint": "sha256:45855662b25ac7d2b8172f9041c0c97703107f5ef451739a970e59b0291dd644", "assurance": { "status": "unreviewed", "scope": "evidence-passport-revision", "statement": "AI-assisted structural preparation. This revision has not been reviewed by a human or subject-matter expert.", "machineChecks": [ "schema", "publication-diff-contract", "material-project-fingerprint", "claim-text-drift", "source-reference-resolution", "complete-source-dossier", "snapshot-hash" ] }, "projectState": { "status": "live", "outcome": "ongoing", "evidenceGrade": "peer-reviewed", "timeline": { "started": 2020, "ended": null } }, "governance": { "operator": "London borough councils (Active Travel Fund / DfT)", "actorTypes": [ "city-government" ], "fundingModel": "grant", "fundingDescription": null, "cost": null, "ownership": null, "decisionRights": null, "exitConditions": null }, "claims": [ { "id": "clm-2379fa7c8fb29a72", "field": "impact", "text": "motor traffic inside fell by close to half on average, with little net displacement onto boundary roads", "statementKind": "descriptive", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-58258fe870131247" ], "supportNote": "Thomas & Aldred report an average reduction of roughly 47% in motor traffic inside London LTNs, with little evidence of displacement to boundary roads.", "caveat": "Averages conceal variation — some individual boundary roads saw traffic rise.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } } ], "sources": [ { "id": "src-2dead611ed8f37f7", "title": "Active Travel Academy (University of Westminster) — London LTN dataset", "url": "https://blog.westminster.ac.uk/ata/projects/london-ltn-dataset/", "publisher": { "name": null, "domain": "blog.westminster.ac.uk", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "background", "claimRefs": [], "temporal": { "publishedAt": "2024-07-01", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Authoritative independent dataset: 113 LTNs covering ~40 km2 implemented in London, 27 removed by end-June 2024, typically after protest, negative consultation or political change.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-58258fe870131247", "title": "Thomas & Aldred (2024), Changes in motor traffic in London's Low Traffic Neighbourhoods and boundary roads — Case Studies on Transport Policy", "url": "https://www.sciencedirect.com/science/article/pii/S2213624X23001785", "publisher": { "name": null, "domain": "sciencedirect.com", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-2379fa7c8fb29a72" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Peer-reviewed. Large average traffic reduction inside LTNs (reported ~46.9%) with little evidence of displacement onto boundary roads. (Page 403s to automated fetch; existence and findings confirmed via WestminsterResearch record and multiple independent summaries.)", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-7bd112b4433a38a7", "title": "DfT / Ipsos UK — Low Traffic Neighbourhoods Research report (March 2024)", "url": "https://assets.publishing.service.gov.uk/media/65f400adfa18510011011787/low-traffic-neighbourhoods-research-report.pdf", "publisher": { "name": null, "domain": "assets.publishing.service.gov.uk", "classification": "not-classified" }, "sourceType": "pdf", "language": "und", "role": "background", "claimRefs": [], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Independent government-commissioned review across London, Birmingham, Wigan, York: traffic reduced inside, adverse boundary-road impacts limited; twice as many residents supported (45%) as opposed (21%); nationally ~18% of schemes removed.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-8dc29c583d8e5566", "title": "BBC News — Lambeth LTN to be removed immediately, court rules", "url": "https://www.bbc.co.uk/news/articles/c4ge92xldrjo", "publisher": { "name": null, "domain": "bbc.co.uk", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "background", "claimRefs": [], "temporal": { "publishedAt": "2025-06-04", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-20", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Established-press coverage of the controversy: a London LTN ordered removed by the courts, illustrating the legal and political contestation around camera-enforced schemes.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } } ], "coverage": { "claimsTotal": 1, "claimsMapped": 1, "sourcesTotal": 4, "sourcesUsedByClaims": 1, "sourcesWithPublicationDate": 2, "sourcesWithArchive": 0, "sourcesWithExactLocator": 0, "sourcesWithContentHash": 0 }, "limits": [ "Publisher names and source languages have not yet been classified; domains are recorded without guessing.", "Existing source notes are descriptive locators, not page- or paragraph-exact citations.", "A missing archive, publication date or content hash is shown as null rather than inferred.", "The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim." ] } }, { "id": "2026-08-26-claim-mapping", "createdAt": "2026-08-26T19:00:00Z", "effectiveAt": "2026-07-25", "changeType": "update", "summary": "Added a six-claim evidence mapping and a sourced lesson; corrected the attribution of the 113-scheme figure, which belongs to the London dataset and a 2025 casualty study, not to the traffic meta-analysis, whose sample is 46 schemes in 11 boroughs; added that peer-reviewed casualty study and the government review's own removal and support figures.", "preparedBy": { "type": "automation", "label": "AI-assisted evidence preparation", "humanApproved": false }, "review": { "status": "unreviewed", "by": null, "date": null, "note": "Awaiting operator and domain-expert review; publication of this revision implies neither." }, "changes": [ { "operation": "replace", "path": "/snapshot/projectFingerprint", "summary": "Updated projectFingerprint to the current sourced project record." }, { "operation": "replace", "path": "/snapshot/claims", "summary": "Updated claims to the current sourced project record." }, { "operation": "replace", "path": "/snapshot/sources", "summary": "Updated sources to the current sourced project record." } ], "snapshotHash": "sha256:c5f51a0444b6dd84c36ec88947ace98333d1b9203eed689f571009b631f8c1b9", "snapshot": { "asOf": "2026-07-25", "projectFingerprint": "sha256:574e1cf85ac22506ec8b0e81a1e325c154095132085ee03fe9d2cb541e1eda00", "assurance": { "status": "unreviewed", "scope": "evidence-passport-revision", "statement": "AI-assisted structural preparation. This revision has not been reviewed by a human or subject-matter expert.", "machineChecks": [ "schema", "publication-diff-contract", "material-project-fingerprint", "claim-text-drift", "source-reference-resolution", "complete-source-dossier", "snapshot-hash" ] }, "projectState": { "status": "live", "outcome": "ongoing", "evidenceGrade": "peer-reviewed", "timeline": { "started": 2020, "ended": null } }, "governance": { "operator": "London borough councils (Active Travel Fund / DfT)", "actorTypes": [ "city-government" ], "fundingModel": "grant", "fundingDescription": null, "cost": null, "ownership": null, "decisionRights": null, "exitConditions": null }, "claims": [ { "id": "clm-34d2a67d27a8d1f6", "field": "snippet", "text": "By June 2024, 113 LTNs covering 40 square kilometres had been implemented in London and 27 of them had been removed, typically after public protest, a negative consultation or a change in the borough's political leadership", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-ed85fded46ca3418", "src-2dead611ed8f37f7" ], "supportNote": "The study states the counts directly and names the three usual reasons for removal, citing the University of Westminster dataset that the Active Travel Academy publishes.", "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-48e17519328f3dd7", "field": "snippet", "text": "one was ordered out by a court in 2025", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-8dc29c583d8e5566" ], "supportNote": "The broadcaster reports a court ordering a Lambeth LTN removed immediately.", "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-da97c9e17ce7f8ee", "field": "impact", "text": "A peer-reviewed meta-analysis of monitoring data from 46 schemes in 11 boroughs found mean motor traffic on internal roads falling from 1,780 to 930 vehicles, against a projected 1,745 if background trends had held, and only a marginal association with traffic volume on boundary roads", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-58258fe870131247" ], "supportNote": "The paper meta-analyses monitoring reports for 46 schemes in 11 boroughs and gives exactly these means, alongside the finding that the schemes are only marginally associated with change on boundary roads.", "caveat": "Elsevier blocks automated retrieval of the full text; the figures are taken from the published abstract.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-7ebf60ee9dbcdeba", "field": "impact", "text": "A second peer-reviewed study, using police-reported casualty data for all 113 London LTNs, found a 14% reduction in casualties at junctions between newly filtered minor roads and the surrounding major roads (95% CI −21% to −8%)", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-ed85fded46ca3418" ], "supportNote": "The study reports exactly this estimate and confidence interval from police casualty data for 2012-2024.", "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-47bbb5e3b3e075a0", "field": "impact", "text": "The government's own commissioned review across four English areas found 82% of schemes still in place and 18% removed, with 45% of residents supporting their local scheme against a lower share opposed", "statementKind": "quantitative", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-7bd112b4433a38a7" ], "supportNote": "The commissioned report's summary states that 82% of LTN schemes remain in place with 18% subsequently removed, and that support across the four areas was 45%, with a higher proportion supportive than opposed in every area.", "caveat": "The figures cover four English areas — London, Birmingham, Wigan and York — not London alone. The PDF's text layer is letter-spaced, so a text search inside it may not match the printed wording.", "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } }, { "id": "clm-2d2d83f9b47e6027", "field": "lesson", "text": "the removals track protest, consultation results and changes of administration rather than measurements", "statementKind": "descriptive", "textMode": "verbatim-from-project-record", "mappingStatus": "mapped", "sourceRefs": [ "src-ed85fded46ca3418" ], "supportNote": "The study names public protest, negative consultation responses and changes in political leadership as the typical reasons for removal.", "caveat": null, "interpretation": { "added": false, "interpolation": false, "note": "The passport copies the published claim and its recorded source mapping without adding a conclusion." } } ], "sources": [ { "id": "src-2dead611ed8f37f7", "title": "Active Travel Academy (University of Westminster) — London LTN dataset", "url": "https://blog.westminster.ac.uk/ata/projects/london-ltn-dataset/", "publisher": { "name": null, "domain": "blog.westminster.ac.uk", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-34d2a67d27a8d1f6" ], "temporal": { "publishedAt": "2024-07-01", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-26", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Authoritative independent dataset: 113 LTNs covering ~40 km2 implemented in London, 27 removed by end-June 2024, typically after protest, negative consultation or political change.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-58258fe870131247", "title": "Thomas & Aldred (2024), Changes in motor traffic in London's Low Traffic Neighbourhoods and boundary roads — Case Studies on Transport Policy", "url": "https://www.sciencedirect.com/science/article/pii/S2213624X23001785", "publisher": { "name": null, "domain": "sciencedirect.com", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-da97c9e17ce7f8ee" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-26", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Peer-reviewed. Large average traffic reduction inside LTNs (reported ~46.9%) with little evidence of displacement onto boundary roads. (Page 403s to automated fetch; existence and findings confirmed via WestminsterResearch record and multiple independent summaries.)", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-7bd112b4433a38a7", "title": "DfT / Ipsos UK — Low Traffic Neighbourhoods Research report (March 2024)", "url": "https://assets.publishing.service.gov.uk/media/65f400adfa18510011011787/low-traffic-neighbourhoods-research-report.pdf", "publisher": { "name": null, "domain": "assets.publishing.service.gov.uk", "classification": "not-classified" }, "sourceType": "pdf", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-47bbb5e3b3e075a0" ], "temporal": { "publishedAt": null, "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-26", "retrievedAt": null, "status": "record-date-only" }, "locator": { "type": "descriptive-source-note", "value": "Independent government-commissioned review across London, Birmingham, Wigan, York: traffic reduced inside, adverse boundary-road impacts limited; twice as many residents supported (45%) as opposed (21%); nationally ~18% of schemes removed.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-8dc29c583d8e5566", "title": "BBC News — Lambeth LTN to be removed immediately, court rules", "url": "https://www.bbc.co.uk/news/articles/c4ge92xldrjo", "publisher": { "name": null, "domain": "bbc.co.uk", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-48e17519328f3dd7" ], "temporal": { "publishedAt": "2025-06-04", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-26", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Established-press coverage of the controversy: a London LTN ordered removed by the courts, illustrating the legal and political contestation around camera-enforced schemes.", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } }, { "id": "src-ed85fded46ca3418", "title": "Furlong, Fevyer, Casement, Aldred, Laverty, Armstrong, Edwards & Goodman — Removing Through-traffic on Minor Roads Reduces Road Danger at Junctions with Surrounding Major Roads, Findings (21 Aug 2025), peer-reviewed", "url": "https://findingspress.org/article/143455-removing-through-traffic-on-minor-roads-reduces-road-danger-at-junctions-with-surrounding-major-roads", "publisher": { "name": null, "domain": "findingspress.org", "classification": "not-classified" }, "sourceType": "web-page", "language": "und", "role": "claim-evidence", "claimRefs": [ "clm-34d2a67d27a8d1f6", "clm-7ebf60ee9dbcdeba", "clm-2d2d83f9b47e6027" ], "temporal": { "publishedAt": "2025-08-21", "updatedAt": null, "sourceCheckedAt": null, "recordLastVerifiedAt": "2026-07-25", "dossierCreatedAt": "2026-08-26", "retrievedAt": null, "status": "publication-and-record-dates-recorded" }, "locator": { "type": "descriptive-source-note", "value": "Open-access peer-reviewed study using police casualty data 2012-2024 across all 113 London LTNs. Carries both the corpus figures — 113 LTNs covering 40 km2 implemented by June 2024, 27 since removed, typically after protest, a negative consultation or political change — and the safety result: a 14% reduction in casualties at junctions between newly filtered minor roads and surrounding major roads (95% CI -21% to -8%).", "exact": false }, "preservation": { "archiveUrl": null, "archivedAt": null, "contentHash": null, "status": "not-captured" } } ], "coverage": { "claimsTotal": 6, "claimsMapped": 6, "sourcesTotal": 5, "sourcesUsedByClaims": 5, "sourcesWithPublicationDate": 3, "sourcesWithArchive": 0, "sourcesWithExactLocator": 0, "sourcesWithContentHash": 0 }, "limits": [ "Publisher names and source languages have not yet been classified; domains are recorded without guessing.", "Existing source notes are descriptive locators, not page- or paragraph-exact citations.", "A missing archive, publication date or content hash is shown as null rather than inferred.", "The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim." ] } } ] }