You're both right. In the general case, FISA warrants are court orders sufficient to require a third party to disclose information in their possession. However, any given FISA warrant may not meet the requirements for a warrant that must pass muster under the 4th amendment. They are, however, sufficient for activity that does not require a warrant under the 4th amendment.
So the question is: what requires a warrant that meets the strictures of the 4th amendment? Not every kind of data gathering or information collecting activity requires a warrant.
A good hypothetical to think through is a Tesla car. Tesla has the capability to track you via GPS, though the functionality is apparently disabled on retail models. But say it was enabled, and Tesla collected and stored information about where you went to optimize your ownership experience. Do the police need a warrant to get that information?
On one hand, the police do require a warrant (meeting 4th amendment strictures) to put a GPS on your car (because it is a physical invasion of your private property). On the other hand, police don't need a warrant to ask your neighbors what they know about where you've been.
So: what do the police need to get your GPS information from Tesla? On one hand, you can say that the police shouldn't be able to do indirectly what they can't do directly, and say that they require a warrant meeting 4th amendment strictures to get that information from Tesla. On the other hand you can point to a crucial distinction: the police did not need to invade your physical property to put a GPS bug on you--you did that part yourself and voluntarily told Tesla exactly where you were going. If you had phoned Tesla, and told them exactly where you had went, and they wrote that down and stored it in a file, the police would not have required a 4th amendment warrant to get that data. Just a lesser court order in the event Tesla did not cooperate.
So the question is: what requires a warrant that meets the strictures of the 4th amendment? Not every kind of data gathering or information collecting activity requires a warrant.
A good hypothetical to think through is a Tesla car. Tesla has the capability to track you via GPS, though the functionality is apparently disabled on retail models. But say it was enabled, and Tesla collected and stored information about where you went to optimize your ownership experience. Do the police need a warrant to get that information?
On one hand, the police do require a warrant (meeting 4th amendment strictures) to put a GPS on your car (because it is a physical invasion of your private property). On the other hand, police don't need a warrant to ask your neighbors what they know about where you've been.
So: what do the police need to get your GPS information from Tesla? On one hand, you can say that the police shouldn't be able to do indirectly what they can't do directly, and say that they require a warrant meeting 4th amendment strictures to get that information from Tesla. On the other hand you can point to a crucial distinction: the police did not need to invade your physical property to put a GPS bug on you--you did that part yourself and voluntarily told Tesla exactly where you were going. If you had phoned Tesla, and told them exactly where you had went, and they wrote that down and stored it in a file, the police would not have required a 4th amendment warrant to get that data. Just a lesser court order in the event Tesla did not cooperate.