Tower dumps like the ones described there (that example was from 2010) became very restricted, legally, in mid 2018. As the article points out, that area of the law was always constitutionally "murky," to use their term. Courts eventually ruled that LE can no longer do "fishing expeditions" where they scour the dump data for any and all cell phones in the vicinity in order to develop suspects. But they can still look for specific numbers of known individuals for whom they've shown probable cause in legal warrants (what's likely been done or will be done in the Summer Wells case if foul play ends up being a factor). It's more complicated, obviously, than what I described here but that's the basic gist of it. Delphi has the unique problem where they may have collected tower dump data originally in 2017 but after the rulings in 2018 can no longer legally use it at trial ("fruit of the poison tree"). I have other thoughts on this topic but it's better put into the Delphi thread. All MOO.