mostly scale: accumulation of data over time and use of that data (a single brief observation of an anonymous person vs identification and observation of a person over time, with real-time activities reported to law enforcement). same way that it's unacceptable/illegal for a police officer - without probable cause or a warrant - to follow you down the street to your home, then wait outside your home and follow you 24/7, recording all your activities which exist in the public sphere, then putting you on a departmental watchlist where your protected activities are broadcast to all officers in real-time.
you may be ok with that ("i don't have anything to hide", "i trust the police/government", "the free market will prevent abuses [by companies like Dataminr]" are some rebuttals i've heard recently), but it undermines our constitutional rights, setting a dangerous precedent and chilling free speech/association (per the ACLU). additionally, how else is this collected information being used by the police and Dataminr? what are their retention policies? what other kinds of analysis are being done (fta, there seems to be a not-insignificant number of false positives)?
> mostly scale: accumulation of data over time and use of that data
I'm a long-time, hardcore civil libertarian so I share your concerns about potential law enforcement abuse. However, in the instance being cited here, I'm not seeing a clear violation of 4th amendment rights. Posting on openly shared social media is not only public speech, these days it's advertising and promotion. I assume you wouldn't have a problem with law enforcement subscribing to a press release monitoring service that would notify them if someone is sends out media press releases promoting their protest in that agency's jurisdiction. Arguably, not having any situational awareness of open-to-the-public mass gatherings planned in their area might be something they'd even be blamed for if overcrowding turned into a public safety situation at a book signing or something and they were oblivious.
So, while I want to restrict police overreach as much as possible, the challenge is in how we might craft guidelines of what's allowable vs not allowable which are clear and consistent.
you may be ok with that ("i don't have anything to hide", "i trust the police/government", "the free market will prevent abuses [by companies like Dataminr]" are some rebuttals i've heard recently), but it undermines our constitutional rights, setting a dangerous precedent and chilling free speech/association (per the ACLU). additionally, how else is this collected information being used by the police and Dataminr? what are their retention policies? what other kinds of analysis are being done (fta, there seems to be a not-insignificant number of false positives)?