California tenant rights case law scraper — CourtListener-first, SQLite-backed, with topic tagging, outcome detection, and domain-tuned relevance scoring for unpermitted-unit / RSO / landlord-harassment research
You came here because some landlord rented you a converted garage with no certificate of occupancy and now thinks he's entitled to keep your money. He is not. Sit down. I'm going to explain how this works.
This is a Python scraper. It crawls California case law for tenant rights cases — unpermitted units, RSO violations, rent disgorgement, landlord harassment, the whole sorry parade. It puts the results in a SQLite database so you can actually find what you're looking for instead of clicking around for six hours like a person who doesn't value their own time.
I don't have time for nonsense and neither do you. Let's go.
- Pulls cases from CourtListener. That's the primary source. It works.
- Tries Justia as a fallback, but only if you ask nicely with
--include-justia. It's slow. I warned you. - Tries Caselaw Access Project out of habit. Harvard pulled the plug in 2024. The scraper notices and moves on. So should you.
- Tags every case with topics. Twenty-one of them. Things like
unpermitted_unit,rent_disgorgement,rso_coverage. You know. The good stuff. - Scores each case for relevance so the on-point ones float to the top and the contract dispute about a koi pond sinks where it belongs.
- Detects who won. Tenant, landlord, dismissed, settled. If the opinion doesn't say, it says "unknown." Honesty. Try it sometime.
You need a CourtListener API token. It's free. Don't whine.
https://www.courtlistener.com/sign-in/
uv sync --extra justia # or just `uv sync` if you don't want Justiacp .env.example .env
# Now open .env and paste your token. Don't email it to me.source .envIf you see a 403 error, your token is missing or expired. That's not a bug. That's you.
How to use it
uv run python scraper.py --search "unpermitted unit RSO" --after 2020-01-01uv run python scraper.py --run-all --after 2018-01-01uv run python scraper.py --cite "Carter v. Cohen"uv run python scraper.py --cite-alluv run python scraper.py --reportuv run python scraper.py --export-json
uv run python scraper.py --export-csvEverything goes into tenant_case_law.db. Re-running a search never overwrites good data with bad data — the scoring uses MAX semantics. I built it that way because I know what you're like.
The seed cases you should already know
If you're researching unpermitted-unit cases and you don't recognize these names, close this README and go read them first. Come back when you're ready.
┌─────────────────────────────┬───────────────────────┬──────────────────────────────────────────────────────────┐
│ Case │ Cite │ Why it matters │
├─────────────────────────────┼───────────────────────┼──────────────────────────────────────────────────────────┤
│ Carter v. Cohen │ 188 Cal.App.4th 1038 │ Rent disgorgement + treble damages + attorney fees on an │
│ │ (2010) │ unpermitted unit. The big one. │
├─────────────────────────────┼───────────────────────┼──────────────────────────────────────────────────────────┤
│ North 7th Street Associates │ 7 Cal.App.5th Supp. 1 │ Zero rent obligation. UD dismissed. Tenant gets fees. │
│ v. Constante │ (2016) │ │
├─────────────────────────────┼───────────────────────┼──────────────────────────────────────────────────────────┤
│ Gruzen v. Henry │ 84 Cal.App.3d 517 │ The landlord cannot collect rent on an unpermitted unit. │
│ │ (1978) │ Period. │
├─────────────────────────────┼───────────────────────┼──────────────────────────────────────────────────────────┤
│ Salazar v. Maradeaga │ 10 Cal.App.4th Supp. │ RSO relocation required even when the unit is illegal. │
│ │ 1 (1992) │ │
├─────────────────────────────┼───────────────────────┼──────────────────────────────────────────────────────────┤
│ Combiner v. Swartz │ 167 Cal.App.4th 1365 │ The landlord cannot wiggle out of the RSO by claiming │
│ │ (2008) │ you "agreed" to it. │
└─────────────────────────────┴───────────────────────┴──────────────────────────────────────────────────────────┘A word about Justia
Justia is opt-in for a reason. Their search endpoint requires a login now, so the scraper has to fetch every case page and filter the text itself. That's slow. It also used to have a bug where it would keep every case that contained the word "unit" — which, in California real-property law, is every case. That's been fixed. The filter now requires all non-stopword query terms to match, and there's a stub guard that throws out anything under 1KB because that's almost certainly a Cloudflare interstitial pretending to be an opinion.
If you turn it on with --include-justia, you'll see a line like:
[JUS] fetched=240 kept=12 filtered_out=221 stubs=7That's the filter working. If kept ever looks suspiciously close to fetched, something has regressed and I want to know about it.
What's in the box
scraper.py # The whole show. ~970 lines. Single file. Deal with it.
requirements.txt # For pip people.
pyproject.toml # For uv people. We prefer uv people.
.env.example # The template. Copy this. Don't commit the real one.
README.md # You are here.
CLAUDE.md # Notes for the AI assistant. You can ignore it.
tenant_case_law.db # The database. Created on first run. Gitignored.Things I do not want to hear
- "It's not finding any cases." → Did you set CL_API_TOKEN?
- "Justia isn't working." → Did you uv sync --extra justia?
- "The database is huge." → It's case law. Of course it is.
- "Can it scrape Google Scholar?" → No. They'd ban us in an hour.
- "Why is the score for my case only 0.4?" → Because it's only sort of relevant.
That's the whole point.License
Use it. Don't sue anybody with it that doesn't deserve it. And for the love of God, read the cases before you cite them.
Final word
I built this so people who got pushed around by slumlords could find the law that protects them. If that's you — good. Get to work. The cases are out there and now you have a flashlight.
Order. Order in the court.
— adapted from the bench, with apologies to the actual Honorable Judith Sheindlin, who would never write Python