Since its taxpayers money, any custom made software for gov MUST be FOSS or we can equally abandon any logic whatsoever - citizens payed for it, gov employees were working with implementation team on shaping it, so it belongs to them. This doesn't have to be so for supportive domains such as databases but I would personally prefer that also (i.e. Postgresql instead Oracle db). There are many more reasons for this the…
This is why Free Software Foundation Europe created a petition to make all publicly paid code public: https://publiccode.eu.