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Generative AI for in-house counsel: What it is and what it can do for you

Sterling Miller

23 Feb 2024

The artificial intelligence (AI) tools for legal professionals released over the past several years have left a lot to be desired. Many were interesting but all lacked the “that’s amazing!” AI moment. Until now. And unless you have been living on the moon for the past year or so, you know that GenAI has come to dominate technology headlines, not only in the business world generally but also in the world of legal services where, for perhaps the first time, people are starting to ask if lawyers can survive this technological tsunami. Below we discuss generative AI and how in-house legal departments will be affected.  

Jump to:

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What is artificial intelligence?

 The prompt

What’s going on now and why?

What can generative AI do right now?

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How it works

Ethical dilemmas and AI

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Robot lawyer army?

What should I do next?

What is artificial intelligence?

The term “artificial intelligence” can be a bit misleading, at least when it comes to the legal field. Artificial intelligence is an umbrella term to describe technologies that rely on data to make decisions. For purposes of legal work, a better description is “cognitive computing.” Cognitive computing uses AI systems that simulate human thought to solve problems using neural networks and other technology. Cognitive tools are trained, rather than programmed; they learn how to complete tasks traditionally done by people. Think of a legal-trained AI as a research assistant who can sift through the hay and find the needle. Why is this important? Because 328.77 million terabytes of data are created each day. The ability of any human to review and comprehend that amount of data is impossible.  

What’s going on and why now?

In 1965, Gordon Moore made a prediction based on his observation that the number of transistors per square inch on integrated circuits had doubled every year since their invention. This has since become known as “Moore’s Law.” His law predicts that computer power will double roughly every two years while the cost of that computing power goes down. When coupled with the ever-lower cost of data storage, you have the foundation for the rapid rise in AI capabilities and availability. For GenAI, the sudden explosion into our consciousness was caused by decades of scientific work that was finally matched with the right level of raw computer processing power to make it feasible to launch and use such technology. In other words, in late 2022 the technology finally caught up with the thinking.  

As business leaders (and businesses) become adept at using these tools, they will expect the other members of the C-Suite – including general counsel and the legal department – to follow suit. Legal departments, therefore, need to be ready for this change and must adapt quickly to the use of generative AI.     

How it works

For our purposes, artificial intelligence has evolved in three stages, and understanding this evolution is key to understanding the power of generative AI:  

Stage 1 – AI is a computer programmed to mimic human intelligence. At this stage, AI tools can recommend a song you might like, spot spam emails and move them out of your inbox, and even drive a car.  

Stage 2 – On top of general AI came machine learning, a branch of artificial intelligence that allows a computer to learn from data without being specifically programmed. It’s like teaching a computer to play chess. At first, the computer doesn’t know how to play, but it gets better over time as it gets more and more information or experience.  

Stage 3 – Now comes generative AI, which is like Picasso in the world of artificial intelligence. Instead of just learning patterns and making decisions like other versions of AI, it can create new stuff. It can write songs, paint pictures, design graphics, or even draft documents.  

Where lawyers once used AI to extract pertinent information by typing a query directly into the machine, lawyers can now ask it to create things. Because of the power of generative AI to create vs. regurgitate and to interact with the user in ways that mimic human behaviour, lawyers are far more ready to adopt and use these tools than they were five or six years ago when AI first came on the legal scene. The result? Generative AI will become ubiquitous – an indispensable assistant to practically every lawyer.   

Robot lawyer army?

Now comes the question on every lawyer’s mind – will generative AI replace lawyers? We’re sorry to disappoint anyone who has visions of unleashing a horde of mechanical robot lawyers to lay waste to their enemies via a mindless rampage of bone-chilling logic and robo-litigation. That isn’t happening. Instead, what is likely to happen are three things.  

1) Certain legal roles may undergo changes, particularly those primarily focused on tasks such as document review, summarization, or initial legal research, which could see shifts in their responsibilities.  

2) Jobs will be created, including managing and developing generative AI (legal engineers), and writing prompts for AI (prompt engineering).   

3) Most lawyers will be freed from certain mundane tasks and can focus more on work that creates value.  

Moreover, the bar will not allow generative AI to replace lawyers; the practice of law will require humans in a central capacity no matter what. Second, lawyers must validate everything generative AI spits out. Third, generative AI does not understand context, nor can it discern whether it is being used to come up with the answer the user wants vs. the correct legal answer. Only people can do that. And fourth, when it comes to serious legal work, most clients will want to talk to a person, not a chatbot.   

Generative AI should – eventually – make your life easier and allow legal departments to increase efficiency without adding (or cutting) headcount and without having to invest large sums of money. It will be another tool you can use to streamline tasks and reduce the amount of mundane work you must deal with.   

The prompt

When it comes to generative AI, the most critical element is the “prompt” you use to get results. Prompts are questions, instructions, or requests that you type into the tool to trigger the process described above. You can ask generative AI multiple questions, make multiple requests as part of one prompt, or refine the results by refining the prompt or adding to the data generative AI is considering. It takes practice and time to get it right. The best way to think of prompts and generative AI is to treat the tool and process like you would treat a young associate or intern: You must brief it on what you want/need, give additional information over the course of the assignment, ask clarifying questions, and, in the end, likely fix the work product.   

Generative AI works by attempting to understand your question (i.e., your “prompt”). Once you prompt it to do “something,” it scans a ton of information and writes the best answer possible based on the data it has access to (just like you do as a lawyer, only at a much slower pace). Here are some simple prompts I have created or found that make it easy to get started:  

  • What is the standard for [set out legal issue] in [x] jurisdiction? 
  • Outline the steps needed to do [y]. 
  • Can you explain the holding in [specific case]? 
  • Create a checklist for… 
  • Draft a contract for [scenario]. 
  • What are the ethical considerations for [specific legal scenario]? 
  • Set out the pros and cons of [x]. 
  • Can you provide cases that discuss [specific legal issue]? 
  • Summarize this agreement and identify the five most important terms. 

What can generative AI do right now?

Here is a short list of some of the things that generative AI can do for in-house lawyers right now:  

  • E-Discovery document review and summaries   
  • Legal research   
  • Draft memoranda, contracts, clauses, email, legal briefs, and motions  
  • M&A due diligence  
  • Simplify text to the right level of understanding  
  • Create checklists   
  • Redline documents   
  • Edit your writing   


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Ethical dilemmas and AI

Let’s cut to the chase: generative AI has no ethics. It’s just a machine. Under the rules of professional responsibility, lawyers have many ethical obligations to comply with, and all of them still apply when using AI. The SRA and other accreditation organisations worldwide have consistently held that GenAI is just another tool that lawyers can and should use when appropriate, but that all output and work product must be vetted and approved by an experienced lawyer.  

What should I do next?

Lawyers are slow to adopt new technology. We are naturally sceptical and see the problems with something new vs. the benefits. But ignoring generative AI is not an option. Here is what legal departments need to do next:  

  • Embrace it. But act with restraint and caution.   
  • Develop legal department and company policies regarding the use of generative AI.  
  • Start small with free products and low-risk tasks (understanding the risks) and get your feet wet. Then move to the more powerful paid version. Finally, look for established companies offering generative AI products and use those to truly establish a foundation for AI use in the legal department, such as Thomson Reuters.   
  • Do it as a team: figure out how best to make generative AI work for everyone in the department.   
  • Keep data privacy and confidentiality concerns top of mind.  
  • Learn how to draft prompts that work for in-house legal research and needs.   
  • Stay up to date. Things are happening fast, and the ground keeps shifting.   
  • Understand your ethical obligations around the use of generative AI.  


While not an expert, you should now have a solid understanding of generative AI, how you can benefit from its use in your legal department, and what steps you should be taking now. It will take a long time for generative AI to live up to all the hype when it comes to legal work, but it will get there. This is truly one of those game-changing moments in history, especially regarding the practice of law. And you have a front-row seat and a part to play.  

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