The proposed secrecy law could even criminalise a "tea lady" who used a classified document lying around in an office, as scrap paper, parliament's committee on the info bill heard.
IFP MP Mario Oriani-Ambrosini said any unauthorised person possessing a classified document would be a criminal.
The ANC said that under the new law anyone who found classified documents had to give these to the police.
Oriani-Ambrosini said a person finding and giving such a document to the police would be a "good Samaritan. A good Samaritan should not be forced with a gun at his head."
ANC MP Luwellyn Landers said the bill was about theft of state secrets, not top-secret documents lying around.
ANC MP Annelize van Wyk said the opposition should "be careful of creating the impression that the state is negligent".
"Our law does not criminalise you reading a top-secret document - all it says is that you must return it," said Landers.
Oriani-Ambrosini said a state secret may be leaked to so many people it could not be considered a secret any more, even if it was still classified.
If a secret had "gone viral" it would be pointless to prosecute people who passed it on. "Then it is gone - let it go."
The DA said people should not be prosecuted for disclosing the contents of classified documents that revealed corruption; or a likely and serious public safety or environmental risk; or if the document was classified only to save someone from being embarrassed.
Handing classified documents to the police instead of going public with them would "amount to a cover-up", said DA MP David Maynier. If he were given a classified document proving arms-deal bribery, there was little chance that the police would investigate it.
The ANC proposed a change to oblige the police to investigate any classified document on corruption handed to them.
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