Surrey County Council (SCC) has been warned it faces legal action over the closure of six care homes.
Lawyers said there had been a "complete lack of consideration" by the council of the human rights of those living in the care homes.
They said residents who are moved from their care home had "a significantly increased risk of death".
The council said it had taken the decision to ensure older people "receive the very best care."
SCC said the care homes Brockhurst in Ottershaw, Park Hall in Reigate, Cobgates in Farnham, Dormers in Caterham, Longfield in Cranleigh, and Pinehurst in Camberley were being closed due to the unsuitability of the buildings.
Writing to the council, Gregory Bennett from New Zealand-based Abbey Employment Law Specialists said the process followed by the council was not lawful "in part".
"An important aspect of the decision was the complete lack of consideration by the SCC of the fundamental rights of the residents," Mr Bennett wrote.
He said the council had not considered sufficiently the human rights of the residents.
"There is sufficient evidence to show that elderly residents who are moved from their home (and this relates to care homes) have a significantly increased risk of death," Mr Bennett wrote
He said the legal firm would prefer to meet the council to resolve the matter, but were considering taking legal action.
Surrey County Council spokesman said: "We took this decision because the most important thing is to ensure older people receive the very best care.
"We're helping older people live independently for longer which means increasingly they need complex specialist care and facilities, which these homes can no longer continue to provide."