Dangers of using AI to draft wills

According to a recent survey, almost half of people in the US and UK would trust artificial intelligence (AI) to write their will. It has also been reported that the proportion of wills made by solicitors has fallen below half for the first time as many people are turning to other will drafting services including AI, which is not surprising given that AI is being integrated into nearly every facet of daily life.

We asked Google’s AI assistant Gemini whether AI can be used to prepare a will and it’s answer was very telling as it acknowledged its own limitations:

“While AI can assist in drafting wills by  generating standard clauses and providing basic information, it cannot fully replace the expertise of a legal professional in creating a personalised and legally sound will…potentially leading to unintended consequences or disputes.”

There are several dangers and risks to be aware of when using AI, or unqualified will writers, to draft your will. These are detailed below.

Lack of personalisation in wills

It is impossible for AI or will writers to replace the expertise and insight of a qualified solicitor who can tailor their advice based on family dynamics, a client’s finances and long-term goals.  It is unlikely that AI or will writers will be able to handle complex estate planning needs, which involve matters such as tax planning strategies, trusts, detailed guardianship provisions or business and agricultural succession planning.

These types of providers simply cannot deal with complex  scenarios, which can have significant consequences such as large inheritance tax bills, accidentally disinheriting a relative or not properly planning for dependents with additional needs.

AI’s lack of insight is perhaps one of the most worrying issues with using AI to prepare legal documents or when relying on it for legal advice. One of AI’s features is that it ‘speaks’ with authority and presents information in a way in which people trust. But that does not mean that it is correct or that it has understood the context of what it is ‘advising’ on.

Context is hugely important in law and understanding the factual matrix of any legal matter is critical for any lawyer. These facts must be applied to the law and the endless practical uncertainties which arise, particularly where there are disputes. Being able to assimilate these and provide accurate and realistic advice is one of the key skills of any lawyer and one which AI is simply less able to do.

Ambiguity and errors in wills

Wills require precise and unambiguous language to prevent disputes. Using AI or unqualified will writers to draft wills can mean vague and conflicting terms are used which can leave executors, beneficiaries and the courts struggling to understand who is entitled to what.

The recent case of Tedford v Clarke & Ors [2025] exemplifies this. The case demonstrates the issues that arise when using an unregulated will writer and the pitfalls of using ambiguous wording. The Judge commented that the will was “drafted badly” and that a will giving rise to so many questions showed the “ignorance of the draughtsman”.

The Judge also commented that the dispute arising in this case had caused the parties “untold anguish, substantial expense and delay, and destroyed family relationships.” This highlights how important it is to use the services of a reputable and experienced legal practitioner for something as important as preparing your will.

It should not be overlooked that most people do not know how AI is producing the answer given to their question, so they are unable to check it or verify it easily. This adds to the risk of errors going unnoticed.

Up-to-date legal knowledge

The law is always changing with amendments to legislation and  taxation changing the legal landscape all the time. A benefit of instructing experts is that they are aware of the latest developments and can advise accordingly based on individual circumstances.

A key example of this is the recent proposed changes to Business Relief and Agricultural  Relief. These changes are likely to have a significant impact on individuals who own agricultural or business property and the reforms need to be monitored closely. It is therefore critical to take appropriate measures to ensure you are getting the best advice.

The limitations of AI’s legal knowledge have been exposed recently in various reported cases. AI has been shown to invent seemingly plausible but non-existent case law. Such hallucinations, as they are known, are a dangerous possible side effect of relying on AI in the legal sphere.

Jurisdictional issues

Additionally, there may be jurisdictional implications which render the wills made by AI or Will writers invalid, potentially leaving the testator partially or fully intestate which can have wide ranging implications.

While some AI tools are highly advanced, they are not experts in the field. Laws governing wills and estates vary significantly between countries, states and municipalities. These laws determine what makes a will valid, such as witnessing protocol, the format of the will and executor requirements. A generic AI generated document may omit jurisdiction-specific formalities rendering a will not fit for purpose or even invalid.

There are also intricate rules in many countries around habitual and tax residence, domicile and forced heirship rules, which may change how estates with an international element are dealt with for tax and succession purposes.

If an estate is complicated by international elements, it is even more essential you speak to experts with knowledge of these different jurisdictional rules and how these rules may impact your will to ensure the documents drafted are jurisdictionally compliant.

Data security concerns

Another issue with wills being drafted by AI tools is the data security concerns. You are invariably inputting sensitive personal and financial information into an AI tool without fully understanding how that data is used and stored.

Some tools may store or reuse user data without explicitly asking for consent.  If there is a data breach, then this can expose critical personal information such as addresses, full names and dates of birth putting users at risk.

Additionally, AI platforms may operate in different legal jurisdictions which can lead to uncertainty about which data protection laws apply. Therefore it is imperative to be aware of the information that you are inputting into these AI tools and to be aware of how your data will be handled.

Lack of accountability

Whilst AI platforms often include disclaimers that they are not providing legal advice, if something goes wrong, such as a will is deemed invalid which leads to intestacy, there may be little to no legal recourse.

This is not to say solicitors do not make mistakes, but if they do make a mistake, they can be held accountable for their conduct and should have liability insurance to protect their clients and provide compensation. Having someone to sue when things go wrong is a much overlooked but crucial consideration for people engaging with legal services.

Concluding thoughts

A badly drafted will can cause more harm than good, undermining the very purpose of writing one in the first place. Disputes take time to resolve, depleting the estate through legal fees and reducing what is ultimately passed on to beneficiaries. With proper legal guidance and unambiguous, clear language, you can ensure your wishes are followed and your loved ones are protected from unnecessary conflict.  For these reasons it is best to use a qualified legal professional to prepare your will rather than an unqualified will drafter or, even worse, AI.

Our Estates, Tax & Succession team can help in all aspects of will drafting and our Will, Trust & Estate Disputes team can assist when disputes arise.