The FBI also does intelligence work. What's different is that in Canada the RCMP take in local policing responsibilities where there's no local resources to do so themselves.
CSIS is more analogous to the CIA. It's an intelligence service, not a police service.
But the US have a lot of specialized police agencies -- the RCMP is also the DEA, the Secret Service, the US Marshals... probably many more I'm forgetting or don't even know about.
I decided I'll answer the question even though I don't accept the premise.
* CSIS is a civilian national intelligence service
* RCMP is a national police service
They're related because CSIS was born out of recommendations from the McDonald Commission. After the FLQ crisis, Canada understandably had a bit of a 9/11-style overreaction, and the RCMP Security Services got involved in a number of scandals stemming from overzealous and illegal activities. The RCMP Security Services were consequently abolished and their responsibilities were given to the newly formed CSIS, which was overseen by the newly formed SIRC. One could consequently reasonably say that CSIS was the successor to the RCMP Security Services.
However, it's really impractical for policing to be completely divorced from intelligence work, so much as the FBI does intelligence work despite the US having numerous civilian & military intelligence organizations, the RCMP continue to do intelligence work.
Wow this is like an "evolution isn't real because there's still monkeys" level of response. Try opening a book or Wikipedia or anything and having a gander.
Evolution doesn't say that humans are the "successors" to monkeys.
I grew up in Canada and read the McDonald Commission's report (well some of it), and was there when CSIS was created. Saying it's the "successor" to the RCMP is like saying Canada is the "successor" to Britain.
