>I feel it makes it easy for the law enforcement agencies to track down criminals if they used the SIM card to commit crime.
No, it doesn't. SIM cards registered with false identities are available for about R50 apiece in central Johannesburg, without any need for the buyer to provide identification. The police are aware of this.
>Our government doesn't have history of invading privacy of their citizens, which makes it easier to trust them.
That's naive, there have been a number of stories showing just how badly the government abuses the privacy of ordinary citizens. Amongst these was a story by the Mail and Guardian showing that the government had performed over 6 million electronic intercepts in the first years that RICA was active, along with testimony from current and former intelligence officers stating that they often hid unauthorised intercepts amongst the multitude of authorised ones.
There is also clear evidence that a number of journalists, including two at the Mail and Guardian, have had their phone calls, text message and internet usage intercepted by SA intelligence agencies.
As for authorisation, all the state requires to perform a broad intercept is the say-so of a retired judge appointed and paid by the Minister of Justice. That means that unlike a regular court judge, whose remuneration and service depends on an independent entity in the Judicial Services Commission, the RICA judge is subservient to the Executive.
The access for those intercepts is easy too, given that RICA requires that the major phone companies, internet exchanges and ISPs create real-time data feeds into the various Interception Centres managed by the Office of Interception Centres. This allows them to snoop on the internet and phone traffic of all South Africans in real-time without the need to even inform the companies providing the data.
RICA's main purpose was to make it easier for the state to legally surveil as many people as it wanted to without too much in the way of opposition. It's not a good law.