Does filling U.S. postal service business reply envelopes with junk incur any legal peril?
<p>Some companies that send junk mail include a "business reply" envelope.  This allows the junk mail recipient to send a "reply" through U.S. mail at the originator's expense.</p>

<p>In fact these business reply envelopes can be filled with heavy junk and given to the U.S. Postal Service in order to impose additional postage costs on the junk mailer (perhaps discouraging them from further junk mailing).  If a person did that could he be found liable for damages in a civil action?  Or does it run afoul of any criminal statute?  Are there any examples of either?</p>

<p>Two questions. Since the answer to the second answers the first I will go out of order</p>

<blockquote>
  <p>If a person did that could he be found liable for damages in a civil action? <strong>Or does it run afoul of any criminal statute?</strong></p>
</blockquote>

<p>As far as the post office is concerned, per <a href="https://pe.usps.com/text/dmm300/505.htm" rel="nofollow noreferrer">Domestic Mail Manual 505 1.3.1</a> your heavy boxes shipped Business Reply Mail (BRM) are considered waste. Mailing the box with BRM as a label would not be a crime as long as you did not improperly ship prohibited items, like ammunition, or were trying to commit another crime such as sending a bomb or drugs through the mail, but it would be thrown out or returned to you. See: <a href="https://pe.usps.com/text/csr/ps-086.htm" rel="nofollow noreferrer">customer support ruling</a></p>

<blockquote>
  <p><strong>If a person did that could he be found liable for damages in a civil action?</strong> Or does it run afoul of any criminal statute?</p>
</blockquote>

<p>Unless you wasted the post offices time with excessive bulk mailings of junk or any of the reasons given before, not likely.</p>

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