The truth is: Your home is your castle. And as a homeowner and as long you haven't done anything illegal, you have the right to kick anyone (including the Police and the FBI) off of your property if you feel that they are unwelcome in your home. Unless, the Police or the FBI have a legal and official reason for being there (by warrant or other executive order), you can legally order them to leave your property. If they don't comply, you have the authority to have them forcefully removed from your property (trespass them).
People are going to go to jail or get killed listening to this crap.
There
are lawful reasons for police to enter your premises without a warrant (or "other executive order," whatever that is). Exigent circumstances come to mind first. If they are on your property, lawfully, but without warrant, and you tell them to leave, they are going nowhere. If you attempt to forcefully remove them, they will arrest you. If, in your moral (but misplaced) indignation, you resist, you will be forcefully subdued. Then, if you think this is a legitimate self-defense situation, and decide to kill one of the officers (as has been suggested by another poster in another thread), I see one of three outcomes for you: (1) in jail for the rest of your natural life, (2) in jail until your natural life is ended by chemicals introduced by a state-ordered needle, or (3) (most likely) dead on-the-spot.
The legal analysis of trespassing LEOs in the performance of their duty is a helluva lot more complicated than a bunch of IANALs will try to make it seem. Since consulting a lawyer while you are in the middle of it, you need a plan that will both protect your rights AND not get you killed.
IANAL and am not offering legal advice. I am just warning you to get REAL legal advice before following the "trespass the cops" crap.
What would I do? First, I'd never assume that, without a warrant, the LEOs have no justifiable reason to be on my property and that I can (forcefully or otherwise) kick them off. Much like with an encounter on the street, I'd try to ascertain whether the action was lawful. Failing that, I'd proceed as though it was lawful, getting my objections on the record.
For example, if a group of officers knocked on my door and demanded entry, I'd ask them for ID and a warrant. If they produce a warrant, I'd inspect it, allow them in if it had my address on it, and either way, I'd contact a lawyer immediately. If they did not have a warrant, I'd tell them that I do not consent to any searches, that I will not invite them into my home, and that I want them to leave my property.
If they do not go and insist on coming in,
I do not know whether their actions are lawful or not, so I will inform them that I still do not consent, but will not resist.
Of course, everything will be recorded. Rights violations can be fixed later. Dead can't.
There is exercising your rights intelligently; then there is being stubbornly and stupidly getting yourself justifiably jailed or killed. Choose wisely. And "wisely" ain't listening to a bunch of IANALs on telling you how to man up when faced with a bunch of armed officers.