The exercise of self-determination is a human right; however, for people with dementia (PWD), progressive physical and cognitive impairment negatively affects their decision-making processes. For PWD, it is often relatives who make such decisions. This qualitative study included interviews with sixteen relatives of PWD who live in nursing homes. Research questions are as follows: How do relatives understand the participation of PWD who live in nursing homes? How do co-researchers understand participation and the role of relatives? A co-researcher was consulted when the questions were designed. During the interviews with relatives, photos were used to stimulate discussion. Critical situations in nursing homes were discussed with relatives and later interpreted together with a co-researcher. The findings included an understanding of how relatives played a key role in PWD; however, relatives were concerned that PWD were unable to take part in decisions. In addition, relatives named ways that nursing homes opposed human rights, and the co-researchers also highlighted situations that conflicted with human rights. Classifying dementia as a disability at the policy level could strengthen the rights issues of PWD. The key findings of the study are essential for social workers arranging for placement of PWD in nursing homes.