How many of you have read any of the user agreements we have with Google or Facebook? Neither have I. Why are legal contracts so “notoriously difficult for non-lawyers to understand?” A new study in Cognition provides some clues.
This is perhaps the clearest piece of legal writing we have:
“You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to an attorney. If you cannot afford an attorney, one will be provided for you. Do you understand the rights I have just read to you? With these rights in mind, do you wish to speak to me?” 
Fortunately, few of us have to hear those lines, so why is it that most of the legal documents we see, contracts for rent or mortgage, let alone those user agreements, seem so difficult to understand? To search for underlying causes, the researchers identified five characteristics of legal writing that were difficult to process.
- NON-STANDARD CAPITALIZATION TO MAKE DISCLAIMERS AND LIMITATIONS “CONSPICUOUS”
- Use of infrequently used, archaic words, e.g., herein
- Choosing jargon rather than common phrases
- Center-embedding convoluted syntax and definitions in the middle of sentences 
- The use of the passive versus active voice – I ate a chicken sandwich vs. A chicken sandwich was eaten by me
“lawyers have a habit of frequently inserting long definitions in the middle of sentences.”
Using a word analysis algorithm, the researchers compared these constructs to phrases found in standard contracts, court opinions, and non-legal writings, including the Wall Street Journal, blogs, movies, etc.
- 78% more words were capitalized in legal vs. non-legal text
- 2.5-fold more jargon and infrequent word choices
- 2.5-fold more center-embedding
- 4-fold more use of the passive voice
Having demonstrated that legalese differs from English in terms of writing, the researchers then looked at how these stylistic touches impacted comprehension. They created short paragraphs with identical content, but one set written in legalese, the other without those “features.” The subject matter was standard concerns of contracts, the provisions, liability and warranty, and jurisdiction and means of resolving differences.
The study involved 100 participants asked to review six scenarios (“3 legalese, 3 simple”). All were self-reported native English users, and all were assessed as to their “language experience.” 
- Higher language experience was associated with greater comprehension
- Comprehension was reduced for legalese both without and with a delay in asking about the meaning
- Recall was reduced for legalese
- Center-embedded phrases and low word frequency choices were the drivers of incomprehension
In their discussion, the researchers ask whether our ability to understand legal documents is hindered more by our lack of knowledge regarding legal concepts - “law is a system built upon expert knowledge of technical concepts, such as habeas corpus, promissory estoppel, and voir dire” or that these documents are poorly written - “law is a system built upon ordinary concepts,” such as cause, consent, and best interest.”
They believe their results point to the latter, that jargon and sentence structure impede comprehension more than the concepts trying to be conveyed. Of their arguments for why lawyers write in this manner, the one that seems to be most persuasive is the need for “communicative precision.” Words have specific meanings in court, so we can’t fault lawyers for using them in legal documents. But we can insist on plain text explanations, and we should.
“Making legal language more straightforward would help people understand their rights and obligations better, and therefore be less susceptible to being unnecessarily punished or not being able to benefit from their entitled rights,”
Eric Martinez, lead author
 The original text was written by Assistant Attorney General (California) Doris Maier and Nevada County D.A. Harold Berliner in 1966. Berliner saw a business opportunity and produced a durable card that police officers could carry.
 Center-embedding - “In the event that any payment or benefit by the Company (all such payments and benefits, including the payments and benefits under Section 3(a) hereof, being hereinafter referred to as the ‘Total Payments’), would be subject to excise tax, then the cash severance payments shall be reduced.” Simplified - In the event that any payment or benefit by the Company would be subject to excise tax, then the cash severance payments shall be reduced. All payments and benefits by the Company shall hereinafter be referred to as the ‘Total Payments.’ This includes the payments and benefits under Section 3(a) hereof.”
 The participants took an Author Recognition Test where they were given lists of names and asked to identify authors among them. This served as a proxy for language exposure.
Source: Poor writing, not specialized concepts, drives processing difficulty in legal language Cognition DOI: 10.1016/j.cognition.2022.105070