Margaret Haywood worked undercover on the Panorama documentary
A former colleague of a nurse who took part in secret filming for a BBC documentary at a Brighton hospital has said he felt betrayed by her actions.
Margaret Haywood, 58, of Liverpool, is answering disciplinary charges at the Nursing and Midwifery Council over her role in the Panorama show in July 2005.
Undercover Nurse was televised to expose failures in care for the elderly at the Royal Sussex County Hospital.
Martin Johnson told the hearing on Wednesday: "I was disappointed."
He added: "I believed she took me into her confidence - I felt betrayed."
Ms Haywood denies that her fitness to practise is impaired by reason of misconduct.
She also denies that she failed to assist colleagues when a patient had a seizure on the Peel and Stewart ward.
But she has admitted a charge of breaching patient confidentiality.
The allegations are said to have taken place between 3 November 2004 and 5 May 2005 while Ms Haywood was working as a registered nurse for Brighton and Sussex University Hospitals NHS Trust.
Dr Karen Johnson, for Ms Haywood, accused the trust of failing to act until the Panorama programme.
She said the nurse had been proactive in raising serious issues of concern.
"The concerns were of an exceptionally serious nature and it was fully justified to approach the media...in order to raise those issues of concern," she said.
"As a result of the programme conditions did improve for patients.
"On that basis I would ask you to accept that the involvement of Margaret Haywood was fully justified and therefore she has no case to answer."
Dr Johnson said that while another senior nurse dealt with the patient who was having a fit, Ms Haywood could not assist because the area around the patient was cramped and Ms Haywood had a "difficult relationship" with the colleague concerned.
Earlier Carol Harris, who became ward sister on the Peel and Stewart ward in March 2005, described problems on the ward and praised Ms Haywood as a "reliable" nurse who had pointed out some concerns about patient care to her.
Mrs Harris said paperwork relating to patients and care plans was "very hit and miss but overall the standard was appalling".
The four-day hearing continues.