Is Sword and a Shield a doctrine in the US?
<p>I'm working on a complaint to US federal agencies. One of the arguments I need to make is, a company cannot use existing laws or policies or instruments as both a sword and a shield. That is, they cannot apply an instrument as a defensible position in one circumstance, and then use the same instrument for offense in another circumstance.</p>

<p>I know US law does not favor dual uses like that. For example, in the <a href="http://www.databreach-settlement.com/" rel="nofollow noreferrer">Anthem Data Breach settlement</a>, Anthem tried to use security evaluation reports for defense by saying, <em>"security firms that performed the evaluations said everything was OK"</em> [sic]. Then, Anthem tried to say the reports were not discoverable because it was protected work production. Judge Koh disagreed and ordered the Anthem to turn over the reports stating Anthem could not use them as a sword and a shield.</p>

<p>My question is, is sword and shield a doctrine in US law? If not, then what is it called?</p>

<p>(I'm getting lots of hits explaining the concept, but I'm not finding the legal underpinnings).</p>

<h2>No</h2>

<p>The term "sword and shield" is allegorical rather than legal and may be called up in any number of contexts. Such as ...</p>

<h2>Waiver of privilege</h2>

<p>In the particular instance, Anthem was claiming that the reports were privileged and hence protected from discovery, presumably because they were prepared in contemplation of litigation - this litigation, one supposes.</p>

<p>However, privilege is lost or waived if the privileged information is disclosed, as it was by relying on the conclusion of the report in its defense. As such, the entire suite of reports is no longer protected. Basically, if you want to keep privilege you have to keep what is privileged secret. Note, the could have lost privilege if they had disclosed the findings of the report in any way such as by press release or by simply leaving the document in a public place.</p>

<p>In this context, the judge is stating that they cannot use the "shield" of privilege to protect a report that they have used as a "sword" to make a attack their opponent.</p>

<p>There is such a thing as a "sword and shield" doctrine in U.S. law, and indeed there are several of them, but each of them is restricted to very particular kinds of situation. It is not a general doctrine that applies in circumstances as broad as you describe.</p>

<p>For example, there are a number of defenses to an action to quiet title (e.g. unclean hands on the part of a party) that can be used to prevent another party from having title to real estate established in that party's name, but cannot be used to establish title to that real property in your own name.</p>

<p>Similarly, if you assert that a document is privileged from discovery or being offered as evidence in a dispute, you cannot use that document to prove your case without waiving that privilege.</p>

<p>But, your description:</p>

<blockquote>
  <p>One of the arguments I need to make is, a company cannot use existing
  laws or policies or instruments as both a sword and a shield. That is,
  they cannot apply an instrument as a defensible position in one
  circumstance, and then use the same instrument for offense in another
  circumstance</p>
</blockquote>

<p>is not an accurate statement of the doctrine, or more correctly, is not an accurate description of any of the several specific doctrines described with the phrase.</p>

united-states definition