A criminal investigation is under way into a general practitioner and an orthopaedic surgeon after the audit office found evidence suggesting collusion between doctors and prison officers over falsifying sick leave certificates.

The office referred its findings to the attorney-general’s office, and a departmental official has since given a statement to investigators naming the two doctors under scrutiny.

The referral follows a special report on the prisons department issued in March this year which examined prison staff sick leave records covering 2022 to 2024.

Speaking to Politis, auditor-general Andreas Papaconstantinou said the findings, which pointed to “serious suspicions of collusion between doctors and prison officers“, had been passed to the competent authorities for further investigation.

Investigators identified 171 individuals who exceeded the statutory threshold of 42 days of sick leave in at least one of the three years examined.

Of those, 44 exceeded the threshold in the last two years and 34 did so in all three.

Attention centred on eight prison officers who had been absent for between 43 and 229 days a year and who collectively submitted dozens of certificates issued by the same two doctors.

In one case an officer absent for 205 days in 2023 and 202 days in 2024 submitted some 111 certificates over the two-year period.

Of these, 105 certificates, around 94 per cent came from the two doctors now under investigation.

The audit office cross checked the certificates against visit records held by the health insurance organisation (HIO) with the national health service (Gesy).

For four of the eight officers the general practitioner was listed as their personal doctor, yet a substantial number of certificates had no corresponding recorded visit.

For the remaining four, the doctor was not their registered GP at all, and certificates were still issued without any visit being logged.

Five of the eight officers also submitted certificates from the orthopaedic surgeon.

In one instance an officer produced 54 certificates while only six visits appeared in Gesy’s system, of which just three matched the certificate dates and diagnoses.

Investigators also found cases where the recorded visit took place after the certificate had already been issued.

The report drew attention to the fact that several certificates issued by the general practitioner concerned orthopaedic conditions, including arthritis, sprains, knee injuries and neck pain.

In one case the orthopaedic surgeon issued a certificate citing “migraine” as the diagnosis.

A separate sample review of absences between January 2023 and May 2025 found that a number of officers delayed submitting their certificates, despite prison rules requiring papers to be handed in by the next working day.

The office said these delays prevented timely referral to the medical board, meaning assessors were often unable to verify whether the officer was genuinely ill at the time leave was granted.