A facial surgeon has been struck off the medical register to "protect the public" after harming his patients.
Roger Bainton carried out dozens of unnecessary operations and "experimental procedures" while working at Royal Stoke University Hospital from 2005 to 2013.
In the 1990s he was severely reprimanded by the General Medical Council over a death in Scotland.
Lawyers are asking why he was ever hired by the Staffordshire hospital.
The trust said he was employed in line with due process and its own policy.
Solicitor Karen Reynolds, who is acting for 55 of his patients, said: "I think there are clear indications that Mr Bainton has been treating patients and damaging patients for decades."
The surgeon rebuilt the faces of assault or accident victims.
A report by the Royal College of Surgeons showed in some cases he used an unproven and experimental bone substitute, called DBX, to treat damaged and fractured eye sockets.
He also carried out "unnecessary surgery" on people with jaw injuries, it said.
A Medical Practitoners' Council panel concluded: "Mr Bainton routinely persisted in attempting surgery rather than adopting conservative treatment and repeatedly undertook procedures which were not clinically indicated."
He was suspended by University Hospitals of North Midlands in February 2013.
Lawyers are questioning why he was ever appointed, after being sacked and reprimanded following the death of patient Iain Duncan at Aberdeen Royal Infirmary in 1995.
The 33-year-old patient suffered a heart attack 48 hours after his operation and died months later. Following investigations, Mr Bainton was found guilty of serious professional misconduct.
'Sacked and reprimanded'
The Staffordshire trust identified 88 patients whose treatment was suspect, but lawyers said he might have harmed many more.
"He was employed by the Aberdeen trust and had been sacked and reprimanded over the death of a patient," said Mrs Reynolds.
"North Midlands knew about all of that and yet appointed Mr Bainton, but then failed to properly monitor him."
The hospital said it had reviewed his appointment and added it "had been undertaken in line with due process and Trust policy".
It said colleagues had raised concerns about him " in a clear demonstration of their commitment to the highest quality of patient care".