The Fourth Amendment is Great!

The Ellison dissent brings up an excellent point with which I largely agree. Law enforcement and other agencies ought not constantly surveil people and collect information without justification beyond the post 9/11 Ashcroft policy of ‘surveil anyone who might have, might currently, or possibly will commit a crime’ (read: everyone); allowing the FBI to investigate everything and everyone with no specified purpose is harmful - it’s akin to saying that everyone could be a potential enemy to the state, a bad precedent to set, and likely would discourage people from participating in legitimate communications and consuming content which, out of context, could be misused.
In applying the Fourth Amendment, government and law enforcement must keep in mind whether a reasonable person would grant this person a tight to privacy; back to Ellison, if that the car was legally parked, then the driver has a right to privacy (driving is a ubiquitous form of transport, essential to daily life), but if the car was doing anything illegal, even something as innocuous as idling in a no parking zone, then it is not unreasonable for the police to use their databases to search an individual - the law must be enforced, and looking up an individual’s information is a prerequisite in appropriately enforcing a law. Thus, the discovery of firearms in the Ellison case is a legitimate one and not poison fruit.
Applying this principle to the Internet, governments maintaining working with companies like ChoicePoint is not kosher; maintaining active records on everyone’s activities is unnecessary. As terrible as the threat of a terrorist attack would be, the point that data analysis on some database which contained every bit of information on everyone’s lives could have prevented 9/11 and so therefore we must use it in the future seems misleading; yes, this tactic probably could have worked, but so conceivably could have other, less Fourth Amendment violating measures. That said, the government can and ought to subpoena an ISP or email provider if they have reasonable suspicion that is validated by a judge.
I believe that the government ought to employ computer matching techniques to study behavior; agencies ought to study the information available to them to prevent fraud and work more efficiently. My issue is the relative ease with which agencies can share and disseminate personal records without an individual’s consent. Under the Privacy Act, an individual is entitled to determine what information relating to him a government agency can collect, use, and spread among other agencies and allows an individual to prevent agencies from spreading information to other agencies without his consent. The CMPPA update to the Privacy Act undermines its original purpose in protecting an individual’s information; the CMPPA grants agencies authority in sharing information within the government and relegates citizens to a position where they can only request information on agreements between agencies; individuals, then, have a greatly diminished, if any, voice on these decisions. When an individual discloses information to a government agency, they maintain a reasonable expectation of privacy over this information; for example, someone who gives up his medical records to a federal agency to qualify for Medicare would not expect another government agency or branch which could employ the individual in the future to peek into that information.
Also, I think the earlier mentioned point which Solove also supports calling for an expectation of accuracy in databases is an unnecessary one; 1-the managers of these databases are incentivized to maintain accurate records (it is their job) and as technology makes updating these databases simpler, these errors will be less common and practically nonexistent; 2-though the Fourth Amendment draws no specific line between law enforcement and the maintainers of these records, precedent has interpreted the Fourth Amendment as a restraint on law enforcement, and so imposing the Fourth Amendment restraint on an otherwise rule-adherent officer seems unfair and, from a pragmatism standpoint, unnecessarily limits the effectiveness of law enforcement. Ultimately, allowing cases of faulty database information like Evans to go forward will not lead to overzealous officers and not undermine the Fourth Amendment - by nature of the situation, the police must be acting by the book.
Also, I found it hilarious that the Department of Defense Total Information Awareness database project was led by someone called ‘Admiral Poindexter.’ Just saying.

Question: Solove makes an odd point at one point during his digital dossiers text - he says that ‘mere subpoenas’ as a means to access information is terribly insufficient and lacks judicial oversight - but aren’t subpoenas instances where a judge oversees and ensures the legality of police procedures? Is his issue that the standards for a subpoena are too low, or is it another issue?