What do you think the film "I Am Sam" is trying to say about the issue of disability?

In I Am Sam, a developmentally disabled man (Sam) fights for custody of his young daughter (Lucy). It is argued that Sam is too disabled to properly care for Lucy, who has already surpassed Sam in terms of intellectual capability. However, Sam is shown to take good care of Lucy, both physically and emotionally, and Sam has a close group of friends who help him raise her. Ultimately, the film asks us: what does it mean to be a parent, and can a disabled person, like Sam, be trusted with the care of a child? Does Sam's disability, and his resultant dependence on others, mean he cannot be a "real" parent? 

Mike Oliver, a disability studies theorist, argues for a social model of disability. He posits that the experience of disability is never solely a product of one's condition, whatever it may be; rather, it is mediated by society's reaction to, and attitude toward, disabled people. If, for example, a person uses a wheelchair, that person may have trouble navigating a large city. According to the social model of disability, it is not that person's disability which hampers their movement, but rather a lack of wheelchair-accessible buildings and public transportation. Such accommodations would enable that person to participate in daily life. Thus, disability activists seek to change prevailing societal attitudes about disability, and promote those changes and accommodations which would elevate and empower people with disabilities.

It can be argued that I Am Sam promotes such a viewpoint. At the end of the film, Lucy's foster parents agree to raise Lucy in conjunction with Sam and his group of friends. Rather than forbid Lucy from seeing Sam, or severely limit his role in her life, they recognize how much he loves her, and how valuable that love is; they come to respect Sam, and create a family system which accommodates him. Together, they create a situation in which Sam continues to be an integral part of Lucy's life, and in which his challenges are mediated. This is an excellent, albeit fictional, application of the social model of disability.