You can legislate
"- Free access to public information by the citizen.
- Permanence of public data. - Security of the State and citizens."
Without legislating the end solution. How many government orgainizations have you seen distribute information ONLY in a format that requires expensive SW to view.? There ar always HTML, PDF.
Hence, the requirement could be that certain types of information be distributed in a way (of the orgainisations choosing) that uses a free viewer.
In thie case where maintainance is a concern, you simply need to be able to convert to a different format. I suppose you could have a reqiurement that the generating information be robostly save information in an open format (xml?).