Ad/Marketing Communication

This legal article/report forms part of my ongoing legal commentary on the use of artificial intelligence within the justice system. It supports my work in teaching, lecturing, and writing about AI and the law and is published to promote my practice. Not legal advice. Not Direct/Public Access. All instructions via clerks at Doughty Street Chambers. This legal article concerns AI Law.

Introduction

AI hallucinations and the careful checking of court documents before filing are currently among the most discussed topics in the legal community. My thoughts are here. However, what if you are not sure about whether you opponent has used AI? What if you are concerned about AI Misuse? Should you make the allegation or even the insinuation it was used?

In that regard, a recent ruling from the Appellate Division of the New York Supreme Court caught my attention due to an unusual insinuation about artificial intelligence: Vanguard Construction & Development Co. v 400 Times Square Associates, LLC (2025).

Summary of Legal Issues

The case involved a dispute over a mechanic’s lien which appears to be a legal claim against a property related to unpaid construction work. The main legal question was whether minor technical errors in paperwork could invalidate the claim. The court allowed corrections, deciding the mistakes weren’t significant.

Where Did AI Feature? What was the Alleged AI Misuse?

In this very brief combined opinion, the Appellate Division of the Supreme Court of the State of New York stated:

“We have considered the parties’ remaining contentions and find them unavailing, including respondents’ counsel’s unfounded insinuation that appellant’s counsel “used ChatGPT to write [his] brief” without verifying the accuracy of cited case authorities. The court reminds respondents’ counsel that, as an officer of the court, such representations must be substantiated, and without evidence, these insinuations can undermine trust and damage one’s reputation (see Rules of Prof Conduct [22 NYCRR 1200.00] rule 3.3[a][1]). Counsel’s response at oral argument when questioned about his claim was dismissive and his attempt to defend and modulate his accusatory contention was disingenuous.

Upon review of the cases relied upon by appellant, we find no support for respondents’ counsel’s position.”

Commentary

In my last blog, I focused on the comments of Mr Justice Ritchie in the High Court, who made it clear that relying on AI-generated information without proper checking can lead to negligence claims, wasted costs orders, and all-round serious trouble for clients and lawyers!

That case has sparked serious discussions across all aspects of legal practice. Interestingly, the lawyers I’ve spoken to are primarily focused on avoiding mistakes, whereas technical experts seem keen to explore business opportunities aimed at preventing AI hallucinations and AI misuse. I’m not sure how they would achieve this, but it will be interesting to see what solutions they propose.

Even if such a solution is developed, it seems to me this would not absolve any lawyer of their responsibility to carry out safe and thorough checks.

Additionally, as awareness grows around the issue of AI hallucinations, allegations or insinuations, involving careless use of AI might become more common. This could potentially lead to an increase in satellite litigation.

However, as the Vanguard Construction case reminds us, such allegations should never be made lightly. Serious allegations “must be substantiated, and without evidence, these insinuations can undermine trust and damage one’s reputation.” I can foresee the courts in England and Wales adopting a similar approach, and so it would be prudent to adopt extreme caution before making any allegations or even insinuations of this kind.

In short, even though AI introduces new complexities, the core issue remains unchanged. Lawyers still have the fundamental responsibility to thoroughly check their sources, whether digital or traditional. We all need to strike the right balance: taking allegations of careless AI use seriously and ensuring the court is not misled, while equally exercising care and restraint in asserting AI involvement unless there is a proper factual basis.

As we all become more accustomed to these tools, their benefits and weaknesses, we should find it much easier to navigate their appropriate use and identify genuine issues, however, we must not forget that making unsubstantiated allegations against any court user could have profound consequences, not just for those making them, but also for their clients and their own reputation.

This article is part of my broader legal commentary available through my Substack newsletter.
Subscribing ensures you receive immediate updates, in-depth analysis, and exclusive legal insights as they are published.
➔ [Subscribe here to stay informed].