If police can't confiscate any evidence without your consent, how would they collect evidence before it's destroyed? Sure, destroying evidence is a crime, but h

If police can't confiscate any evidence without your consent, how would they collect evidence before it's destroyed? Sure, destroying evidence is a crime, but how can the police prove that it was criminal evidence at all? Police: Your honor, when we stopped him, the suspect had 5 years of financial books showing his money laundering in the back of his car. We told him to bring it to court. Suspect: Naaa, that was my daughter's homework, and it accidentally blew out my car window when I was driving home. Sorry about the litter, I deserve that $500 littering fine.