PACER
PACER — Public Access to Court Electronic Records — is the US federal judiciary's official system for public access to docket and filing data. These guides cover how it works, how to query it programmatically, and how DocketLayer's agent-native API compares to the alternatives.
Federal Courts, PACER & CM/ECF: a Developer's Guide
Federal court data is some of the most valuable structured information in the US — and some of the hardest to access programmatically.
This guide explains how the federal court system is organized across 94 district courts, 90 bankruptcy courts, and 13 circuit courts, what PACER is and how it works, and what CM/ECF is and why each court runs its own instance.
It also covers why this data matters for any AI agent operating in legal, financial, or compliance workflows.
94 district courts. 90 bankruptcy courts. Each runs its own CM/ECF instance. No unified API exists — until now.
PACER Developer's Guide →Why is the most valuable federal data in the US also the hardest to reach?
94 district courts. 90 bankruptcy courts. Each runs its own CM/ECF instance. No unified API exists — until now.
PACER Developer's Guide →How to Query PACER Programmatically
PACER has no REST API. Programmatic access requires scraping 184 separate court-hosted CM/ECF instances, each with its own URL, session management, and HTML structure.
This guide walks through what that actually involves — authenticating with the central PACER login, managing session tokens that expire, querying court-specific docket reports, and parsing HTML that differs by jurisdiction.
It also explains when it makes more sense to use an abstraction layer instead.
184 court instances. No JSON. HTML parsing that varies per court. Session tokens that expire at 60 minutes.
How to Query PACER Programmatically →What does it take to query PACER directly — and should you?
184 court instances. No JSON. HTML parsing that varies per court. Session tokens that expire at 60 minutes.
How to Query PACER Programmatically →Federal Case Number Format: a Complete Reference
Federal case numbers encode the court division, year filed, case type, and sequence number in a compact string.
The format is consistent enough to parse programmatically, but has edge cases by court type and jurisdiction that matter when building automated systems.
This reference covers the standard format, all case type codes, variations across district and bankruptcy courts, and how to use case IDs with DocketLayer.
Division, year, case type, sequence. Decode it once, parse federal case IDs forever.
Federal Case Number Format →What does 1:24-cv-01234 actually mean?
Division, year, case type, sequence. Decode it once, parse federal case IDs forever.
Federal Case Number Format →Highest-Volume Federal Courts: Where the Litigation Is
The federal court system has 184 courts, but litigation is not evenly distributed.
A small number of jurisdictions handle the majority of commercially significant cases — the securities fraud suits, the major corporate bankruptcies, the tech patent battles, the large criminal prosecutions.
For AI agents monitoring litigation, credit risk, or regulatory activity, these are the courts that matter most. DocketLayer's launch coverage targets exactly these jurisdictions.
SDNY. Delaware. NDCA. CACD. If the case matters, odds are it's filed in one of these.
Highest-Volume Federal Courts →Out of 184 federal courts, which ones actually carry the weight?
SDNY. Delaware. NDCA. CACD. If the case matters, odds are it's filed in one of these.
Highest-Volume Federal Courts →PACER vs CourtListener vs DocketLayer: Which to Use
Three sources dominate programmatic access to federal court data: PACER, the official government system; CourtListener, the nonprofit archive built by the Free Law Project; and DocketLayer, an agent-native API built for automated workflows.
They serve different needs.
This comparison walks through all three across access model, data freshness, cost, ease of integration, and fit for automated monitoring — so you can choose the right tool before you build.
PACER is authoritative but human-only. CourtListener is free but lags. DocketLayer: ≤15-minute freshness, JSON, built-in change detection.
PACER vs CourtListener vs DocketLayer →Three ways to reach federal dockets. Which one fits your workflow?
PACER is authoritative but human-only. CourtListener is free but lags. DocketLayer: ≤15-minute freshness, JSON, built-in change detection.
PACER vs CourtListener vs DocketLayer →