Elderly man with dementia looking at notes

Understanding Legal Capacity and Dementia

Russell Manning Attorney March 28, 2023

Contesting a will can be a complex legal matter. That is why understanding legal capacity and dementia can become key considerations when contesting a will. Challenging a will based on legal incapacity as a result of dementia requires a clear understanding of its legal basis.  

My firm, Russell Manning Attorney at Law provides trusted legal advice for those looking to contest a will based on legal incapacity in Corpus Christi, Texas, throughout South Texas and the Coastal Bend Areas. Also, people in Bee, Kleberg, Nueces, Live Oak, Jim Wells, Aransas, and Victoria Counties can count on my firm to deliver high-quality estate planning services.

Eligibility to Contest a Will in Texas 

According to data from the National Institute on Aging, about 390,000 Texans currently live with Alzheimer’s disease. This figure highlights the unfortunate prevalence of mental incapacity. As a result, taking proactive steps to deal with this situation is crucial.  

In Texas, a person can contest a will if they have legal standing and can provide evidence of one or more grounds for contesting the will. Here are some of the grounds for contesting a will: 

Lack of Testamentary Capacity 

A will can be contested if the person making the will, known as the testator, did not have the mental capacity to understand the nature and effect of the will at the time it was executed. This may include conditions such as dementia, mental illness, or disability. Anyone who has a financial interest in the estate and can prove that the testator lacked testamentary capacity may have standing to contest the will. 

Undue Influence 

A will can be contested if the testator was unduly influenced by someone to create the will in a way that does not reflect their true wishes. Undue influence can occur when someone exercises control over the testator through coercion, manipulation, or other means. Anyone standing to inherit under a prior will or the laws of intestacy may have standing to contest a will on the grounds of undue influence. 


A will can be contested if the testator was deceived or tricked into creating the will in a way that does not reflect their true wishes. For example, someone may have misrepresented the contents of the will or withheld information from the testator.   


A will can be contested if it does not meet the formal requirements for execution under Texas law. For example, the will may not have been signed or witnessed properly. Anyone who would inherit under the will, if it were found to be invalid, may have standing to contest the will on formality grounds. 

Defining “Legal Capacity” in Texas 

In Texas, "legal capacity" refers to a person's ability to make legally binding decisions and to be responsible for their actions. Legal capacity is important in various legal contexts, including estate planning, guardianship, and contracts.  

Legal capacity may be determined based on a person's age, mental and physical abilities, and other factors. In Texas, a person who is 18 years or older is generally considered to have the legal capacity to make decisions and enter into contracts. However, there may be exceptions for certain types of contracts, such as contracts involving minors, and for certain circumstances, such as mental incapacity due to illness or disability.  

Regarding estate planning, legal capacity is crucial because a person must have the mental capacity to understand the nature and effect of their decisions when creating a will or other estate planning documents. This situation means that the person must have the ability to understand the extent of their property, the assets in question, and the consequences of their decisions. If a person lacks legal capacity when creating an estate plan, the plan may be subject to challenge on the grounds that the person did not have the necessary mental capacity.  

In addition, it is also important because a court may appoint a guardian to make decisions on behalf of an incapacitated person unable to make decisions for themselves. The court will consider the person's mental and physical abilities, their understanding of the consequences of their decisions, and their ability to communicate their wishes when determining whether to appoint a guardian. 

When Is an Individual with Dementia Considered Incapacitated in Texas? 

In Texas, an individual with dementia is considered incapacitated when they no longer have the legal capacity to make decisions and take actions on their own behalf. A person with dementia may be considered incapacitated if they are unable to understand the nature and consequences of their decisions, including decisions related to their medical care, financial affairs, and personal affairs.  

It is vital to note that a diagnosis of dementia does not necessarily mean that a person is incapacitated. A person with dementia may still have legal capacity if they can understand the nature and consequences of their decisions. However, as the disease progresses, the person may become incapacitated and unable to make decisions on their own behalf. 

Seek Trusted Legal Guidance 

At Russell Manning Attorney at Law, I strive to provide compassionate legal counsel regarding mental capacity in estate planning matters. Don’t face complex estate planning matters on your own. Seek trusted legal guidance from an experienced attorney. Contact me today to get the right legal team on your side.