You raise a good question and it deserves a good answer.
The answer is that this government (the way it was designed by our founding fathers) is not welcome to snoop into just anyone's affairs.
This government is (supposed to be) a government of the people, by the people, and for the people.
When the people get together, believing there is an unjust action going on, and petition the government to step in and halt a potential murder until all issues are settled, then the government is doing what it is supposed to do. Follow the will of the people that give it it's power.
Or, have you not read the Constitution?