Staff shortages in the government's payroll team led to maladministration, a report's found.
Tynwald Commissioner for Administration Angela Main Thompson was asked to investigate after a civil servant who held two separate part-time jobs was landed with an unexpected four-figure tax bill.
She found the Office of Human Resources hadn't told the worker they had a right to make a complaint, the time limit for doing so, and how to contact the Commissioner - a breach of its statutory duty.
Her findings, which will be laid before Tynwald in June, also said a lack of staff had also led to maladministration.
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