The findings suggest that the favoritism, instead, is "taste-based discrimination." Men appear to prefer hiring other men.

Flextronics, for instance, said it has taken steps to prevent expert network firms from hiring other employees after the arrest.

Banning bad employers from hiring other vulnerable workers, such as young people, could also send a strong message, Mr Hehir said.

I gave up hiring other people to make them for me; I suddenly realised I can do them myself with paper and scissors.

The unit allows the company to have a say in drilling decisions, oilfield management and even on hiring other Schlumberger units for service contracts.