Is opening a mailbox mail tampering?
Yes, if the mail does not belong to you, then it is mail tampering. According to the United States Postal Inspection Service, tampering can lead to a mail theft complaint. Outright theft, vandalism to the mailbox and tampering are among the reasons you can be charged with a crime.References:U.S. Postal Inspection Service: File a Mail Theft ComplaintResources:U.S.