L.A. Is Quietly Overhauling Its Digital Property Records — Here's How It Stacks Up Against London and Singapore

Los Angeles County's Department of Assessor has been working since January 2025 to scrub tens of thousands of duplicate property images from its public-facing parcel database — a digitization problem that has quietly inflated record counts, slowed permit processing, and caused confusion at city planning counters from Boyle Heights to Canoga Park. The scope of the problem came into sharper focus this spring when the department confirmed it had flagged more than 40,000 duplicate image files tied to assessed parcels across the county's 2.4 million properties.

The issue matters right now for a specific reason. Mayor Karen Bass's housing emergency declaration, still in effect, has accelerated permit approvals for Accessory Dwelling Units across the city. Faster permitting depends on clean, quickly searchable property records. When assessors or contractors pull up a parcel and get three versions of the same roof photograph from different scan dates, it slows processing time — a bottleneck that affordable housing advocates say compounds delays in neighborhoods where ADU construction is most active, including South L.A. and the eastern San Fernando Valley.

What L.A. Is Actually Doing

The county's solution centers on a deduplication protocol developed jointly by the Office of the Assessor and the Los Angeles County Information Systems Advisory Body, a body that coordinates technology policy across county departments. Under the protocol, image hashing — a process that assigns a unique digital fingerprint to each file — is used to identify exact and near-exact duplicates before archiving them in a separate cold-storage repository rather than deleting them outright. The distinction matters legally: property records are subject to California Government Code retention requirements that prevent outright deletion without formal board approval.

The City of Los Angeles Planning Department, a separate entity from the county assessor, runs its own parcel imaging system under the Development Services program headquartered on Figueroa Street downtown. That system had its own duplicate-image backlog, which staff began addressing in late 2024 using off-the-shelf database management software. As of March 2026, the department reported clearing roughly 18,000 redundant files from the PermitLA portal, which contractors and homeowners use to track applications online.

The work is unglamorous and largely invisible to residents. But it has real downstream effects. Processing delays tied to data errors at the Figueroa Street counter contributed to permit approval times that ran an average of 22 days over the city's stated target in the first quarter of 2025, according to a Planning Department performance report published in May 2025.

How Other Cities Are Handling the Same Problem

London and Singapore offer instructive contrasts. The United Kingdom's HM Land Registry completed a multi-year digitization and deduplication project across its national property database in 2023, retiring more than 1.2 million redundant scanned documents as part of the Digital Local Land Charges program. The effort was funded centrally and gave local councils — from Southwark to Sheffield — access to a single, nationally reconciled image repository. That central-funding model is something Los Angeles cannot replicate: California's county-by-county assessor structure means each of the state's 58 counties manages its own records, with no state-level equivalent to Land Registry.

Singapore's Urban Redevelopment Authority, which oversees land records for the city-state's roughly 5.9 million residents, integrated duplicate-image detection directly into its GIS platform in 2022 as part of a broader Smart Nation infrastructure push. The URA system flags duplicates in real time at the point of upload, preventing accumulation rather than requiring periodic cleanup. Los Angeles has no equivalent real-time check in either the county assessor or the city planning system — both still rely on scheduled batch reviews.

Chicago's Cook County Assessor's Office, which faces a data management challenge more comparable in scale to Los Angeles, launched a similar retroactive cleanup in 2023 targeting approximately 60,000 duplicate parcel images. Cook County used a vendor contract with a private GIS firm, an approach L.A. County considered but declined, citing data privacy concerns about sending unredacted property images to a third-party processor.

For Angelenos dealing directly with the system — contractors, title companies, and homeowners pulling permits for ADU projects on streets like Roscoe Boulevard in Panorama City or Vermont Avenue in Harvard Heights — the practical advice is straightforward: if a parcel record looks inconsistent online through the PermitLA portal or the Assessor's property search tool, call the relevant counter directly rather than assuming the digital record is accurate. Both departments say flagged duplicates are still stored and accessible upon request while the cleanup continues, with the county assessor projecting completion of its current deduplication phase by December 2026.