“Well, a lot of the individuals who would end up receiving these notices would be – the onus of proof on what they earned over the period of time, stretching back potentially years, would be a level of proof which they simply would not be able to substantiate. And unemployed people are, almost by definition, they have very vulnerable cohorts within them, and that there would be people who would enter into agreements to repay debts, which they had not incurred in the first place, and I felt that the practice as a result was unethical.”

Source: Robodebt: can you recall a greater failure of public administration? – Pearls and Irritations