Officers enter the house looking for a parolee and found a weapon did they violate the 4th amendment?

Whether officers violated the Fourth Amendment by entering the house depends on the circumstances of their entry. If they had a valid warrant, consent, or exigent circumstances, their search may be lawful. However, if they entered without proper justification, it could be considered an unlawful search and seizure. The presence of the weapon would then be subject to exclusion if the initial entry was unconstitutional.