As digital life grows, governments and agencies want more data – call records, location logs, browsing history, CCTV networks. At the same time, citizens are increasingly aware of their right to privacy. When data retention or mass surveillance laws feel too intrusive, people approach constitutional courts.

Courts usually apply a few essential tests:

• Is there a clear law authorising the surveillance or data collection? Secret, unwritten practices are highly suspect.
  
• Is there a legitimate aim – such as national security, serious crime prevention, or public safety?
  
• Is the measure necessary and proportionate? Collecting everything about everyone “just in case” often fails this test.
  
• Are there safeguards and oversight – like independent review, time limits, audit, and effective remedies?
  

Bulk data retention for long periods, without strong safeguards, creates risk of misuse, profiling, and chilling of free speech. On the other hand, courts also recognise that modern policing and intelligence work require timely access to certain information.

The constitutional challenge is to strike a balance: enough power to keep people safe, but not so much that everyone lives under a digital microscope. Mostly, finely tailored laws with strong checks and balances stand a better chance of surviving judicial scrutiny.