We are guided in this paper by the description of disability articulated in Article 1 of the CRPD:
Persons with disabilities include those who have long-term physical, mental, intellectual or sensory impairments which in interaction with various barriers may hinder their full and effective participation in society on an equal basis with others.
As Michael Stein and Janet Lord note, the CRPD does not directly define the term ‘disability’: “[i]nstead, Article 1 of the Preamble affirms the social construction of disability in which limitations arise from a person’s interaction with environmental barriers rather than as the consequence of an individualized impairment.” This approach reflects a social and human rights model of disability. The model recognizes that it is society’s failure to accommodate the needs of people with disabilities which give rise to the ‘disabling disadvantage’ that people with disabilities encounter in their daily lives, not some inherent mental, sensory or physical condition.
We define the terms ‘intellectual,’ ‘cognitive,’ and ‘psychosocial’ disability as follows. An intellectual disability generally means having greater difficulty than most people with intellectual and adaptive functioning due to a long-term condition that is present at birth or before the age of eighteen. People with this label may have greater difficulty in carrying out everyday activities such as communicating and interacting with others, managing money, doing household activities and attending to personal care. While the term ‘intellectual disability’ is technically distinct from other ‘developmental disabilities’ these terms are often used interchangeably. Cognitive disability refers to similar kinds of difficulties, usually with later onset than age eighteen but which may result from brain injury at an earlier age. People with cognitive disabilities include those who have experienced stroke, dementias or Alzheimer’s disease, and older adults who experience other forms of cognitive decline as they age. People with psychosocial disabilities are those who experience mental health issues, and/or who identify as ‘mental health consumers’, ‘psychiatric survivors,’ or ‘mad.’ These are not mutually exclusive groups. Many people with intellectual or cognitive disabilities, as well as older adults also identify or are identified as having psychosocial disabilities.
B. Legal Capacity and Incapacity
Throughout this paper we refer to the right to ‘legal capacity.’ We also refer to ‘capacity’ laws in Canada, which generally define the cognitive requisites considered necessary for individuals to be recognized as able to exercise legal capacity. In later sections of the paper, to avoid confusion, when we refer to ‘capacity’ as it is defined and used in Canadian law, we sometimes use the convention of placing the term ‘mental’ in front of it in square brackets in order to clarify that our reference to the term is with respect to its usage in law as a descriptor of individual mental/cognitive characteristics considered necessary to exercise legal capacity. Thus, we refer to the right to legal capacity and to criteria of [mental] capacity in Canadian law.
We also refer to ‘legal capacity law’ in Canada, rather than simply to ‘capacity law’ as is the usual case, to clarify that [mental] capacity laws in Canada effectively regulate and allocate the recognition of the right to legal capacity on the basis of certain mental criteria like the ability to understand information and appreciate consequences of a decision.
The term ‘legal capacity’ has a particular meaning in the context of international Conventions and is contained in the Convention on the Elimination of All forms of Discrimination against Women (CEDAW) as well as in the CRPD. It is generally understood in these Conventions as referring to people’s capacity to have rights, and to have the capacity to act on those rights on an equal basis with others without discrimination on the basis of gender or disability. Legal capacity in this sense is a recognized status.
A legal opinion of the International Disability Alliance (“Legal Opinion”) on the article of the CRPD that addresses legal capacity describes legal capacity as consisting of two components: “the capacity to hold a right and the capacity to act and exercise the right…”. International human rights law constructs legal capacity to include both of these elements.  With respect to exercising the right to individual autonomy, which is the focus of this paper, the right to legal capacity means, for example, choosing where and with whom you wish to live, and most importantly, having those choices respected. The concept is relevant to all areas of an individual’s life, including the exercise of legal capacity to enter a contact, to marry, to vote, to deal with property and to make personal life, personal care and health care decisions.
However, this term is not often found in Canadian law. The term ‘capacity’ is much more frequently used in Canadian legislation and is commonly, but not always, defined to refer to an ability to understand information relevant to making a decision and an ability to appreciate the reasonably foreseeable consequences of a decision or lack of decision. In this sense, ‘capacity’ refers to the cognitive requisites considered necessary for exercising one’s right to legal capacity, and having it respected by others.
The term ‘legal capacity’ is not absent from Canadian legal discourse, and is used in the Law Society of Upper Canada’s Rules of Professional Conduct in relation to the concept of having legal capacity to instruct counsel, and also in Ontario’s Human Rights Code, which guarantees to every person having legal capacity a right to contract on equal terms without discrimination. However, the framing of the provision in the Human Rights Code appears to rest on the traditional assumptions of capacity law that some persons are without legal capacity. We challenge this assumption in this paper in light of the CRPD.
The concept of legal capacity is significant because it represents a shift in the understanding that many members of the legal community have attributed to it. A common understanding of legal capacity law in Canada views it in relation to a person’s cognitive functioning. For example, in relation to Ontario’s Substitute Decisions Act (SDA), the Office of the Public Guardian and Trustee’s “Guidelines for Conducting Assessments of Capacity” states the following:
In its legislation, the Government of Ontario has codified the belief that mental capacity is, at its core, a cognitive function. The SDA operationally defines capacity as the ability to understand information relevant to making a decision and appreciate the reasonably foreseeable consequences of a decision or lack of decision. 
Thus, having the status of being considered legally capable is determined based on a person’s own ability to understand information and assess consequences of making a decision. Legal capacity, in this sense, is attached to the attributes of a person. In contrast, legal capacity as it is used in the Convention on the Elimination of All forms of Discrimination against Women and the CRPD is a social and legal status accorded independent of a person’s particular capabilities.
The Legal Opinion illustrates this crucial aspect of legal capacity in its description of what legal capacity means for people who do not have disabilities, as follows:
A non-disabled citizen who owns real estate, or a car, a horse or a book is entitled to sell the house, to hire the car, gift the horse or lend the book.