In my opinion, it is certainly a possible deterrent for the general population, in order to prevent them from at least doing anything that they might regret doing later if they're aware that big brother is watching.
Also, it could possibly be a deterrent to the common criminal only. But for organized crime syndicates, it would not affect them too much, because these criminal minds are very well planned and sophisticated enough to provide their own measures to avoid mass surveillance.
While this may be true for some, I don't see it as being true for all criminals. But this is highly dependent on the area of the world that you're in. If you're in a place like Russia, China, North Korea, etc -- where all of your information is being tracked extensively by groups like the NSA (their equivalent in these countries) and is used against common citizens, you're most likely going to stop committing petty crime because you know the government is using their extensive data on everyone.
In the US, this isn't typically the case. Even if the NSA is able to prove that you're committing some sort of crime, lets say Fraud from your encrypted data that they have a backdoor too, this information isn't shared with Federal/State prosecutors so they don't know this. Information isn't shared between this groups for 'everyday' crimes, but they are shared for activities that are classified as Treason, Terrorist Activities, Etc.
