Note too there are differences in who captures what information, what record there is of the information, and how it is stored, how it is accessed, who has access and under what conditions, and the way it is accessed.
As referenced in linked web pages above
the information CBSA captures, maintains as a "record" as such, or can access, varies . . . including relative to things like mode of travel and status of traveler.
The CBSA Travel History, for example, tends to be in a silo of its own, of sorts, the information that is captured, stored, and accessible, consists of specific fields for which a report can be generated relative to particular individuals. Thus, for a particular "client" (anyone who has been processed in any way in the immigration systems), a report can be generated containing all this information in this silo relating to that client. This is the client's so-called "Travel History."
That barely scratches the surface of what other information has been captured and stored regarding any particular client. It gets complicated, very complicated. A few years ago I shared some research into a remarkably large number of databases maintained just by CBSA and CIC (before the transition to IRCC), and about how many of the databases were linked, overlapped, or otherwise facilitated sharing information. No time to go back and find that research let alone revisit and update it. I am quite confident the scope of information captured, stored, and shared has increased substantially in the intervening years.
In any event, a key element in this is that
IN ADDITION TO INFORMATION IN ANY PARTICULAR SILO, there are protocols for accessing other information which has been captured and stored. Some access is virtually available to prescribed personnel at-will. An officer at a PoE can readily access a client's FOSS, GCMS, even CAIPs records, which in turn facilitate access into other records such as criminal name-history records for the client in either U.S. databases (NCIC/FBI) or Canadian (RCMP). Otherwise access is restricted, with varying degrees or levels of restriction.
A typical ATIP application to CBSA or IRCC will NOT result in a report which includes, for example, the client's name-record criminal history information, even though that information is readily accessible to officers and processing agents in CBSA and IRCC. This is merely one small example.
The point of this is that there can be a HUGE difference in what information CBSA or IRCC accesses versus what it has in individual silos, like the Travel History, like the record or file for processing a particular application (PR card renewal for example). There is a lot of additional information stored in government databases which can be summarily accessed . . . albeit there are of course ethical and privacy policies which specify the circumstances in which an agent or officer can access the information . . . just because a CBSA officer has virtually unrestricted access to client information, it would be improper for the officer to access someone's information unless there is an official reason for doing so (it would be improper to arbitrarily access the system to check on his daughter's boyfriend, for example). Then there are levels of access, some conditioned on the level of authority the officer or agent has, some conditioned on the reason for accessing the information, some require sending a formal inquiry to another agency, some require making a formal request (including statement of grounds) for an investigation.
Thus, as I am wont to do, I have taken the LONG WAY around to an observation I have made many times before:
What information IRCC typically reviews in the ROUTINE case is one thing. What information it can access and review pursuant to making additional inquiry or even investigation is WAY, WAY more.
This is NOT to say IRCC has a crystal ball. IRCC is NOT all-knowing, not by a long shot. BUT IRCC's capacity to find information tends to be far greater than many apprehend. A lot tends to fly by under the radar. But if a client is on their radar for some non-routine reason, the breadth and depth of what IRCC can find out should not be underestimated.
Another important aspect of this is to understand how IRCC uses such additional information. It mostly focuses on discovering possible discrepancies with the client's information. For example, it does not go looking for additional information which shows exit dates in order to reconstruct the client's travel history. It goes looking for information which shows an exit date inconsistent with the client's declared exit dates. Depending on the nature and scope of discrepancies discovered, the impact can be some damage to the client's credibility resulting in elevated scrutiny and some degree of skepticism, or it can result in approaching the client as NOT credible and thus pursuing non-routine process in which more proof from the client is demanded. The impact can go all the way to potentially being grounds for a determination of misrepresentation, even criminal prosecution, again depending on the nature and scope of the discrepancies discovered.
BUT in any event, even if IRCC often overlooks what is even outright fraud,
make no mistake, IRCC has the means to access a lot more information than most apprehend, and these days the chances IRCC will catch a discrepancy are continually increasing. IRCC will not rebuild, let alone build in the first place, a client's travel history, but if the client's travel history is off by much, the odds are substantial IRCC will catch it.