If you expect to be able to keep people from murdering other people, you are going to be extremely disappointed.
Even if the rule was "no murders within 300m over private property", the cost of weapons that can kill you while you sunbathe is falling rapidly. Even if you somehow stop that, there is always the danger that a deorbiting satellite will crash into your house from space on a nice clear sunny day.
There seems to be little point in trying to hold this tide back, so let's make murder legal.
Yeah, not so much.
Laws aren't put in place to make it impossible to commit a crime. Laws are meant to provide a level of punishment that makes the inappropriate behavior no longer worthwhile to a rational person. There will always be some people who still break those laws, but the majority of people will abide by them.