Can SS order an old person to go into residential care against her will? She wants to continue living with her son, but is frail & he is at work during the day. Neither she nor her son want her to be in a care home but she has been taken away despite their wishes. Is this legal? Or maybe I don't have all the facts.
Only if she has been assessed under the Mental Health Act to say she cannot decide herself. That needs doctors and psychiatrists to agree. Otherwise, no.
You say you do not know the full facts, this may be a temporary measure 'respite care' to give time to look for a better option. it could be that they can not organise home care at present so have had to put her in a residential home until it can be resolved.
And the only other option i can think of, is that she has signed another relative or friend up to be her Lasting power of attorney for Health and they have made the decision.