This always makes me wonder why this is even possible in the US. Why can anyone just make an anonymous call and have a death squad kick in someone's door? Sure

This always makes me wonder why this is even possible in the US. Why can anyone just make an anonymous call and have a death squad kick in someone's door? Sure the guy who does the calling is guilty, but why is it so easy to do, shouldn't there be at least some reconnaissance done before you decide to do something so invasive?