<p>There is no dual citizenship for US/China, so no double passports. A US citizen who was a Chinese citizen previously could return, but then would have to give up US citizenship if he wanted Chinese. This is China’s rule, not the USA.</p>
<p>The US doesn’t keep deadbeats out, so on a foreign passport he could get a visa to re-enter the US. However, if he owed taxes and hadn’t paid them there may be a warrant, and he would be stopped entering or exiting the country.</p>
<p>Private banks? I think the person could leave the US permanently without much possibility of being tracked down. If the person had any assets in the US, they could be seized (after court procedures). Of course this would apply to any US citizen who leaves. People skip out all the time on debts. </p>