CASUS
CASUS
Open navigation

Product

Expand Product

Customers

Open Customers menu

Company

Open Company menu

Security

Pricing

CASUS
Open navigation

Product

Expand Product

Customers

Open Customers menu

Company

Open Company menu

Security

Pricing

Casus Logo

CASUS Blog

AI for Lawyers: Use Cases, Risks and Tools

Last updated on

by

Fabian Staub

Fabian Staub

|

Co-Founder & CEO

AI for Lawyers: Use Cases, Risks, and What Law Firms Need to Know

AI is reshaping legal practice faster than most anticipated. For lawyers, the question is no longer whether artificial intelligence is relevant – it is which tools are fit for which tasks, where the risks lie, and what standards of care and data protection apply. This article provides a structured overview: what AI for lawyers can realistically accomplish today, what the research says about its reliability, and what to look for when choosing a tool.

What AI Can Do for Lawyers Today

Contract Review and Risk Analysis

Contract analysis is one of the most established use cases for legal AI. Rather than reading a document linearly, AI-powered tools can systematically identify risks, red flags, and imbalanced clauses - organized by party perspective and severity. The output is a structured list of findings with concrete improvement options, not a generic summary.

Capable legal AI systems go further: they assign risks to the relevant contract parties, prioritize each finding by severity level (low, medium, high), and produce drafting suggestions that can be applied directly in the document. This speeds up review and makes it easier to prepare for contract negotiations.

Benchmarking Against Playbooks and Standards

Another practical use case is comparing a contract against an internal playbook or a recognized best-practice framework - for example, for SPAs, NDAs, or data processing agreements. AI can check whether required clause topics are present and sufficiently detailed, flag missing liability caps, undefined IP ownership, or confidentiality provisions without a deletion duty, and show deviations as risk findings. The output includes recommendations and, in some tools, the option to insert a suitable clause directly at the right location in the document.

Legal Research and Structured First Assessments

Legal AI can also support research - in a structured, source-based way. Instead of generic web searches, specialized tools draw on statutes and case law to produce traceable outputs: argument lines for and against a position, risk assessments, and concrete recommendations such as whether to hold a position, offer a fallback clause, or add a disclaimer.

It is worth noting: even source-based AI research requires human review and legal judgment before it is used in any work product.

Due Diligence and Large-Scale Document Analysis

M&A transactions, compliance reviews, and contract audits often involve dozens or hundreds of documents. AI-powered data room tools can extract defined fields from large document sets in parallel - for example, liability clauses, termination provisions, SLA terms, or IP ownership - and present the results in a structured table. Anomalies and deviations, such as a liability clause without a cap or an unusually long notice period, are flagged and prioritized by risk level. This replaces manual cross-document comparison for many standard extraction tasks.

Proofreading and Document Quality

Before a contract or pleading is sent, formal consistency matters. AI can check cross-references (does section 7.2 actually exist?), flag inconsistently used definitions, identify placeholders and open fields, detect contradictions in terms or deadlines, and ensure spelling conventions are applied correctly throughout. This is not a substitute for substantive legal review - but it is an efficient quality check for documents that are close to final.

Document chat: asking the document

A document chat is valuable when it answers from the specific document rather than from general knowledge. It helps you find information and summarise it cleanly without scrolling through 40 pages: notice periods, liability exclusions, change-of-control clauses, or a compact overview of each party's obligations.

Drafting clauses and inserting them in Word

Writing a clause is rarely the main problem. The time sink is fitting it in: in the right place, in the right style, with consistent terminology, and without breaking the structure of the document. AI becomes useful here only when it integrates changes cleanly into the existing Word workflow instead of just producing text.

Client communication after the review

A review leaves many detailed findings that only become useful to a client once they turn into a clear assessment. AI can produce structured summaries and drafts that present risks and options in an understandable way. The legal judgement stays with the lawyer.

What the Research Says About AI Performance

The evidence on AI vs. lawyer performance is more nuanced than the headlines suggest. A benchmark study published in July 2025 by Vals AI tested over 200 legal questions drawn from US law firms. Specialized legal AI tools scored 74–78% overall; lawyers working without AI assistance scored 69%. In source quality and traceability, legal AI tools also outperformed both ChatGPT and the human lawyers in the study.

An earlier 2023 study found that LLMs trained on contract review tasks performed at the level of junior lawyers, with significantly faster processing times and lower cost per task.

The important caveat: in complex, context-heavy, and multi-jurisdictional questions, lawyers outperformed AI in the studies. AI is a capable tool for structured, repeatable tasks - not a replacement for legal judgment in high-complexity situations.

Risks and Limitations

Hallucinations in General-Purpose AI Tools

The most widely documented risk is hallucination: general-purpose language models produce non-existent case citations, fabricated statutes, and invented legal principles with a high and well-documented error rate. In one widely reported US case, an attorney submitted ChatGPT-generated fictitious case citations in court proceedings. The difference between general AI tools and specialized legal AI lies precisely here: dedicated legal platforms use legally reliable sources and produce traceable, citable outputs rather than plausible-sounding text.

Professional Liability and Duty of Care

Lawyers remain responsible for the quality of their work regardless of the tools used. AI-generated output is an input to legal work - not a substitute for it. Uncritical adoption of AI suggestions without independent review shifts no responsibility away from the lawyer.

Data Protection and Professional Secrecy

Using AI tools that transfer client data to US servers, or that lack clear data handling practices, is difficult to reconcile with professional confidentiality obligations. For Swiss law firms, data hosting in Switzerland or the EU - with no transfer to the US, no human review of documents by the vendor, and no retention of content after processing - is not optional. These are threshold requirements, not differentiators.

Regulatory Landscape

The EU AI Act is now in force and has implications for Swiss firms working with EU clients or EU-related matters. The German Federal Bar Association (BRAK) published a guidance document in January 2025 covering duties of review, transparency, and quality assurance when using AI in legal practice. The document is advisory in nature but reflects the direction of regulatory expectations across European jurisdictions.

What to Look for When Choosing a Legal AI Tool

Not every AI tool is suitable for legal work. Key criteria to consider include:

  • Data hosting: Where is data stored? Is there any transfer to the US?

  • Zero data retention: Is document content stored after processing?

  • No human review: Can vendor-side staff access processed documents?

  • Legal specialization: Is the tool built for legal work, or is it a general-purpose model?

  • Workflow integration: Does the tool work inside existing environments, such as Microsoft Word?

  • Traceability: Are outputs source-based and verifiable?

For Swiss law firms, there is the additional consideration that tools should ideally be hosted in Switzerland or the EU, and should be familiar with Swiss spelling conventions and document standards - which is not a given for international platforms.

Introducing AI in a law firm

Choosing a tool is the smaller part of the work. The larger part is making sure it actually gets used day to day.

Where the effort pays off first

AI pays off fastest on recurring, text-heavy tasks: routine reviews, consistency checks, summaries, and standard clauses. Due diligence and contract portfolio analysis benefit too, because information can be extracted from many documents in parallel. The effect usually shows up as less rework and shorter cycle times. It is most pronounced on standard contracts such as NDAs, data processing agreements, and framework agreements, where patterns and checklists apply well.

Word workflow or chat

For day-to-day firm work, a Word-based workflow is often more efficient, because placement, formatting, and versioning otherwise cost unnecessary time. When changes are applied directly in the document, copy-paste and the usual formatting errors disappear. A chat remains useful alongside it for quick questions, summaries, and explanations.

What team adoption takes

Start with one or two use cases that visibly save time, and define a simple approach everyone can follow. Teams adopt a tool more readily when it works inside the existing workflow and does not add steps. A pilot can often be set up in hours or days. Reaching stable, firm-wide use realistically takes a few weeks, and by then the work sits in standards, roles, and approval processes rather than in the tool.

Taking shadow IT seriously

Where no approved tool is available, people reach for whatever is faster, often without control over where the data goes. In legal work this is particularly sensitive, because confidential documents and client information can quietly end up with third parties. The more effective answer is rarely a ban, but an officially approved tool with clear rules.

AI in Legal Practice: A Realistic Assessment

AI is no longer a promise - it is a productivity tool with documented value for structured legal tasks: contract review, benchmarking, document extraction, research support, and quality assurance before sending. At the same time, AI does not replace substantive legal judgment, and general-purpose tools carry genuine risks in terms of accuracy, hallucination, and data handling.

Responsible AI use in a law firm requires the right tools, clear internal processes, and a critical understanding of where AI outputs end and legal judgment begins. Roughly 40% of a lawyer's tasks are estimated to be routine and repetitive - it is in this category that AI delivers the most consistent and reliable productivity gains.

CASUS: Legal AI Built for Swiss Law Firms

CASUS is a Swiss legal AI platform available as a Microsoft Word add-in and as a web app. All data is hosted in Switzerland or the EU - with no transfer to the US, no human review of documents, and no retention of content after processing. For law firms looking to use AI specifically for contract analysis, benchmarking, due diligence, and document quality - with the compliance requirements that Swiss practice demands - CASUS offers a platform built for that context.

FAQ

What can AI do for lawyers in practice?

AI supports lawyers with structured, repeatable tasks: contract risk analysis, comparison against playbooks or standards, legal research and first assessments, parallel document extraction for due diligence, and formal quality checks before sending documents.

How reliable is AI in legal work?

Specialized legal AI tools use legally reliable sources and produce structured, traceable outputs. General-purpose language models hallucinate at high rates in legal contexts. Regardless of the tool, human review and professional responsibility remain non-negotiable.

Can lawyers use AI to process client documents?

Yes, subject to strict compliance with professional secrecy obligations and applicable data protection law. Key requirements are data hosting in Switzerland or the EU, zero data retention, and exclusion of third-party human access to processed content.

What is the difference between general AI (e.g. ChatGPT) and specialized legal AI?

General-purpose models are not designed for legal precision and frequently hallucinate when asked legal questions. Specialized legal AI tools use legally reliable sources, provide party-aware analysis, and are built around the workflows of legal document work.

What risks does AI use create for law firms?

Core risks include: hallucinations in unspecialized tools, liability from uncritical adoption of AI outputs, professional secrecy violations from insecure data handling, and compliance obligations under the EU AI Act.

Which tasks remain with the lawyer even when using AI?

Strategic judgment, assessment of complex and context-dependent matters, professional liability, and the final review of AI-generated outputs - these remain with the lawyer.

How does legal AI integrate into existing law firm workflows?

Well-designed legal AI tools operate inside existing working environments, such as as a Microsoft Word add-in. This avoids switching between systems and allows changes to be applied in the document with correct formatting in place.

How long does it take to introduce AI in a law firm?

A pilot with one or two use cases can often be set up in hours or days. Reaching stable, consistent use across the team realistically takes a few weeks. The effort then sits less in the tool than in standards, roles, and approval processes.

Does legal AI pay off for small firms?

Teams with high document volume, many versions, and recurring standards benefit most, which often describes small and mid-sized firms. Where resources are tight, freed-up capacity shows quickly because it does not require new hires.

Your Legal AI Associate.

Supported by Innosuisse, the Swiss Innovation Agency
Capterra rating: 5 out of 5
Spin-off from the University of St. Gallen

CASUS Technologies AG Beethovenstrasse 48
8002 Zurich
Switzerland
contact@getcasus.com

Ask your favorite AI about CASUS

ChatGPT
Claude
Perplexity

Your Legal AI Associate.

Supported by Innosuisse, the Swiss Innovation Agency
Capterra rating: 5 out of 5
Spin-off from the University of St. Gallen

CASUS Technologies AG Beethovenstrasse 48
8002 Zurich
Switzerland
contact@getcasus.com

Ask your favorite AI about CASUS

ChatGPT
Claude
Perplexity

Your Legal AI Associate.

Supported by Innosuisse, the Swiss Innovation Agency
Capterra rating: 5 out of 5
Spin-off from the University of St. Gallen

CASUS Technologies AG Beethovenstrasse 48
8002 Zurich
Switzerland
contact@getcasus.com

Ask your favorite AI about CASUS

ChatGPT
Claude
Perplexity