So under the United States constitution the Fourth Amendment requires that the government obtain a warrant before they can go into your house and search for any contraband. In order to do that, they’re required to have probable cause.
Now there are different ways that the government can search your property without a warrant some of those exceptions are if they believe that someone’s in danger, if they believe that there is exigent circumstances. Typically, though, an officer will be required to have probably cause before they can get a warrant to search someone’s house.
Now a person can give consent to law enforcement to be able to search their house that would waive any warrant requirement. So when law enforcement comes to your door and asks to search your property make sure that you are willing to do that because you do not have to give them permission. You can require them to go and get a warrant before you allow them to search your property.