Actually, such a right exists in some cases, in particular, if it&#x27;s found to be a taking.<p><a href="https:&#x2F;&#x2F;www.fas.org&#x2F;sgp&#x2F;crs&#x2F;misc&#x2F;R42635.pdf" rel="nofollow">https:&#x2F;&#x2F;www.fas.org&#x2F;sgp&#x2F;crs&#x2F;misc&#x2F;R42635.pdf</a><p>Additionally, <i>states</i> generally can&#x27;t impair existing contracts through legislation due to the contracts clause.<p>See <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Contract_Clause" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Contract_Clause</a> (mainly because i&#x27;m too lazy to write it all up here).