> The case is People v. Seymour, which involved a tragic home arson that killed several people. Police didn’t have a suspect, so they used a keyword warrant to

> The case is People v. Seymour, which involved a tragic home arson that killed several people. Police didn’t have a suspect, so they used a keyword warrant to ask Google for identifying information on anyone and everyone who searched for variations on the home’s street address in the two weeks prior to the arson. So the warrant required producing information about a small number of Google users. > Like geofence warrants, keyword warrants cast a dragnet that require a provider to search its entire reserve of user data—in this case, queries by one billion Google users. ...but they talk about the total number of people's records Google had to look at to find the small number that satisfied the warrant. I'm not sure why they are bringing that up. As far as I know that's never been relevant when it comes to the 4th amendment. It's the result set that matters, not how many records you had to look at to find that set which can vary greatly depending on just how how you happen to organize your records. E.g., suppose that two rental cars were involved in a crime, one from Hertz and one from Avis. Police know the license numbers of the cars and get warrants to find out who was renting the cars at the time of the crime. Let's also say this was in the days when the records would be paper records in filing cabinets. Let's say Hertz's files are sorted by year and customer name. To find out who had the Hertz car at the time of the crime someone has to just go through all the customer records for the current year looking for the one that had the car. Hertz then ends up looking at the records of about half of the people who rented cars from them so far this year in order to find the one person whose identity the warrant asks for. Let's say Avis's files are sorted by year and car. They just have to go to the current year's records, pull this years file for the car, and then look at the list of customers in that file to see which one had it at the time of the crime. Avis ends up looking at the records of just the people who have rented that one car so far this year to find the one person whose identity the warrant asks for. That's a much smaller number of people's records than Hertz has to look at. Those two warrants would be identical as far as the 4th Amendment goes, because what they are asking for, "who had this particular car at this particular time?", is reasonable. I don't see how it would be any different for records in an electronic database instead of a paper database. The constitutionality of a warrant is not going to turn on whether the query planner can use indexes or has to do a full table scan.