No, but it is my understanding that to even detain a person you need to meet some standard of evidence. I am saying: let the police use whatever lead generating

No, but it is my understanding that to even detain a person you need to meet some standard of evidence. I am saying: let the police use whatever lead generating method they can, as long as they are not using it as evidence to detain, search, or imprison. That is, their system can be whatever they want to generate a list of names. Afterwards, they need evidence to search a persons house, or to detain them, or to arrest them. (In legal lingo: I am okay with them using these methods, as long as they are not considered probable cause https://www.nolo.com/legal-encyclopedia/when-police-can-make-arrest-probable-cause.html https://www.nolo.com/legal-encyclopedia/when-police-can-make...)