The text of a contract can either be long and very explicit, or short but full of implicit assumptions. A DSL is the second kind: you encode those assumptions I the structure of the DSL and the text as written is based on all of those assumptions.
The problem than becomes that anyone who wants to understand the contract now has to read not just the contract as written, but also all of the definition of the DSL itself. This can actually be OK if the DSL is very commonly used, such as a DSL for contracts between two parties which sign new contracts every day.
But it is a huge waste of time for parties which rarely sign contacts, and is often used as an explicit moat to keep laymen from participating. If I give you a contract to sign that isn't even written in plain English, you will have no choice but to hire a lawyer specialized in understanding this contract DSL to advocate for you.
I imagine (savvy) lawyers actually love DSLs that purport to make contracts concise.
If you can't read documents in whatever form for their legal meaning, you can't work around the need for a lawyer. The DSL may be defined in comprehensible enough language and texts in it may be interpretable easily enough; but the method of contract is determined by agreement of its parties (inside the bounds set by law).
Currently, contracts are judged by their meaning in plain English, with any additional definitions being stipulated in the contract itself (either explicitly or as part of the verbal agreements that accompanied the negotiation of the contract).
A DSL is an extra layer of abstraction above that. If you agree to a contract written in some DSL, then you must also agree to the way that DSL translates into plain English. To significantly compress a legal contract that is not deliberately written to obfuscate its meaning, the DSL has to pack a lot of precise meanings into every term, making it very dense and hard to parse unless you're well-versed in it.
That's absolutely not correct. A DSL is not necessarily short and implicit. It can be very implicit or very explicit and the one I worked on was explicit. Its defining feature would be that it is straitjacketed.
The customers in our case did not actually look at the DSL - it was entirely internal. We decompiled the legal document into the DSL so that we could then represent the contract in more understandable ways.
The problem than becomes that anyone who wants to understand the contract now has to read not just the contract as written, but also all of the definition of the DSL itself. This can actually be OK if the DSL is very commonly used, such as a DSL for contracts between two parties which sign new contracts every day.
But it is a huge waste of time for parties which rarely sign contacts, and is often used as an explicit moat to keep laymen from participating. If I give you a contract to sign that isn't even written in plain English, you will have no choice but to hire a lawyer specialized in understanding this contract DSL to advocate for you.
I imagine (savvy) lawyers actually love DSLs that purport to make contracts concise.