Boolean connectors

You do not need connectors. Type a citation, a case name, or a sentence describing your issue and CaseDiver runs all four of its engines at once. Connectors are for the case where you know exactly which words must appear, and where.

Everything below applies to the term engine — the one that reads opinion bodies word by word. Connectors are ignored by citation lookup and case-name matching, which have nothing to do with the words inside the opinion.

Two or more words with nothing between them are treated as all required. There is no implicit OR: a query is a set of conditions the opinion has to satisfy, not a bag of hints.

Common words are dropped from a connector-free query, because they cost recall and buy nothing: the, of, in, is, was, can, and about thirty others. The moment you type any connector this stops — see stemming and noise words.

AND, OR and NOT are connectors only in capital letters. In lowercase they are ordinary search terms.

The rule exists because lawyers write ordinary prose into search boxes. act of god and force majeure clause is a phrase someone means literally, and silently converting its and into an operator would change the question being asked. Requiring capitals means a connector is never an accident.

Proximity connectors are the exception: W/5 and w/5 both work, because there is no English word they could be confused with.

Both terms must appear somewhere in the opinion. They can be a hundred pages apart: AND says nothing about where.

Because a connector-free query already requires every word, negligence AND causation and negligence causation return the same cases. The one thing typing AND changes is that noise-word filtering switches off for the whole query.

Either term satisfies the search. Use it for the several names one doctrine goes by, or for a statutory term and its shorthand.

Excludes opinions containing the term. NOT applies to the single term that follows it, not to the rest of the query.

That last line is the thing to watch. Exclusion is document-wide and absolute: one passing use of the word in an unrelated part of a long opinion is enough to remove it. Prefer narrowing your required terms, or a proximity connector, over excluding a word that might legitimately appear.

To exclude a phrase, quote it: NOT "summary judgment" removes the phrase, while NOT summary judgment excludes only summary and leaves judgment as a required term.

Double quotes require the words in that order, as a unit. Stemming still applies — "clearly established" also matches clearly establishes. This is the most reliable connector on the page and the most under-used. For an unstemmed word form, use #established instead.

A quoted phrase is also a single operand for every other connector, which is what makes multi-word proximity searches possible:

An unclosed quote is read forgivingly: everything after the quotation mark is treated as the phrase. "good faith exception searches for the phrase good faith exception, which is what was almost certainly meant.

Both terms must appear in the same sentence. This is the connector that separates a case that decides your issue from a case that merely mentions both halves of it.

Order does not matter. employer /s negligent and negligent /s employer return the same cases; proximity constrains distance, never sequence. Use a quoted phrase when you need a specific word order.

Both operands also become required terms in their own right, so an opinion missing either word entirely never reaches the proximity check.

Both terms in the same paragraph. Looser than /s and the right choice when a court would state the rule in one sentence and apply it in the next.

As a rule of thumb: reach for /p when a single sentence is too tight to hold both ideas, and for /s when you are hunting for the sentence that states a holding.

Both terms within n words of each other, in either direction. w/5 and the bare form /5 are the same connector.

The distance counts words, and the maximum is 255. Small numbers are more useful than large ones: past about twenty words you are describing a paragraph, and /p says that more clearly.

Worth knowing, because it explains the one behaviour that looks like a bug and is not.

Postgres full-text search has a single positional operator, a fixed word distance, and no concept of a sentence or a paragraph at all. So proximity cannot be answered by the text index alone. CaseDiver handles it in two stages: the index finds opinions containing all the required terms, then the positional constraint is enforced on top of that result — as a tight word span over the opinion body in the primary index (roughly a sentence for /s, roughly a paragraph for /p), or, on the verification path, by splitting the actual opinion text into sentences and paragraphs and checking each candidate.

That text splitter is written for legal prose specifically. A period after F. Supp., Cir., Inc., Stat. or an initial does not end a sentence, so /s does not silently fail on the citation-dense sentences that matter most.

CaseDiver reads a query left to right, once. There is no operator precedence: AND does not bind tighter than OR, and no part of the query is evaluated before another.

Most legal queries are flat runs of terms with the occasional alternatives group, and for those the single pass is exactly right. It matters only when you write something whose meaning depends on grouping.

That happens to be the reading most people intend. But do not rely on precedence to get there — rely on order. Put the alternatives together, and close the group with the required term that follows.

Parentheses are stripped, not honoured. They are accepted so that a query pasted from another platform does not error, and they are read as a hint about where an alternatives group belongs — but they do not create nesting.

If a query genuinely needs nested logic, run the halves as two searches. Two clean result lists you can compare beat one query whose grouping you are guessing at.

Terms are matched with English stemming, so a search for one form of a word finds its other forms. negligent finds negligence and negligently; testify finds testified and testimony. You do not need a truncation character, and there is no wildcard to type.

Stemming applies inside quoted phrases too. A phrase constrains word order and adjacency, not exact spelling.

Noise words — the, of, in, to, is, was, by, with, what, can and about twenty-five others — are dropped from a query that contains no connectors, because on their own they match everything.

The rule in one line: the moment you type any connector, every word you typed is taken literally. If you meant every word, say so with a connector.

Deliberately absent. Each of these either has a better equivalent here or would produce results that only look right.

A CaseDiver search runs up to four engines at once and merges the results. Connectors are instructions to one of them.

Because they run together, a citation in your query is never buried under a loose conceptual match. It also means a connector query and a plain-English query can be mixed: the parts each engine can use are routed to it.

To run the term engine alone, pin the search type to Terms above the search box. Pinning is a real restriction — if a pinned engine has nothing to work with, you get an honest empty result rather than a quiet fallback to a different engine's guesses.

Jurisdiction, court level and date are filters, not query terms. This is not a style preference — putting them in the query text actively produces wrong results.

CaseDiver recognises unambiguous court phrases and lifts them into the jurisdiction filter for you, telling you it has done so. But it lifts only the unambiguous ones: a bare state name is left alone, because Texas Instruments and New York Times are parties, not jurisdictions. Set the jurisdiction with the picker and the ambiguity never arises.

The same goes for dates: use the date filters, including the last 5, 10 and 25 year quick ranges, rather than typing a year into the query. A year in the query text is just a number that appears in the opinion.

Queries that use the connectors the way they are meant to be used.

Try these on the research page →