The police can only break in your door if they have a strong hunch you might be destroying evidence, there is no way they would ever misuse that. Except if you are cooking bacon for breakfast it could be some Hannibal Lecter style destruction of evidence. Have a cold with the sniffles, door comes crashing in because it sounds like you are snorting cocaine (ie. destroying evidence of drug possession). Smoking pot is the same destruction of evidence, heck smoking a cigar could be destruction of evidence of possessing and embargoed good. Any running water, a flushing toilet, using the garbage disposal, grinding coffee, using a blender, basically any noise from your home could be construed as possible destruction of evidence and could bring your door crashing in if a cop felt like it. Thankfully bad things never come of police encounters with law abiding citizens in their own homes.