In "The President's Keepers", released last month, Jacques Pauw paints a vivid picture of Zuma's scandal-tainted presidency including details of how he allegedly packed the State Security Agency (SSA) with loyalists.
The Hawks investigative unit is now considering what charges could be brought against Pauw over his allegations of corruption and misconduct at the top of South Africa's political and security apparatus.
"Based on (the investigation)... we will be able to know who has to be charged or if there are no charges that can be laid against him," Hawks spokesman Hangwani Mulaudzi told the eNCA news channel.
The SSA last week threatened to seek a banning order for the book, which it claims discloses "the identities of the many members and sources of the agency" and its "intelligence collection methods".
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Pauw's work also chronicles how Zuma has purged his adversaries in the political and security establishment since coming to power in 2009.
"I have not revealed any state secrets and have not endangered any operations that are genuinely in the interest of national security," Pauw wrote in the book.
"What I have revealed is an orgy of depravity and venality.