If they have a warrant, they can search for stuff in that warrant.
If they don't, they can still do that, but anything they find will likely not be usable in court and you'll have a straightforward civil rights case.
If they don't, they can still do that, but anything they find will likely not be usable in court and you'll have a straightforward civil rights case.
And... Them stomping on you during an illegal search doesn't make it a legal one and doesn't shield them from liability.
Even in a legal search, I'm guessing they can't decide to curb stomp you just because without the risk of legal/other liability.