>>18929If you've served your "debt to society" (yuck), I don't think the US would prevent you from leaving.
However, it's likely that other countries wouldn't be keen to have you around. For residency purposes, many countries require a police report from your country of origin confirming that you've never been convicted of a serious crime. Depending on what you would have been put on the registry for, not all countries might consider that a serious crime (public urination vs rape, for example) but obviously the cleaner your record the better.
For countries that don't require Americans to obtain a visa (for tourism) before arrival, there's also no requirement to bring a police report, but I don't know if they do some kind of computerized checking once you arrive.
So, depending on your crime and on where you want to go, residency and work visas might be difficult or even impossible to obtain.
Tourist visas would probably be easier, but, again, I don't know which countries do some kind of automated check on you and what for.
There are Americans who have spent decades abroad on tourist visas. They'll live in Taiwan, for example, until their tourist visa expires, take a cheap flight to Thailand for the minimum required period they have to stay away, then go back to Taiwan on another tourist visa. Some people have made this sort of thing work, but it would obviously be a difficult life in many ways, and if you screw up, you could get sent back to the US.
Also, you need some source of income. I assume you're not independently wealthy (or you probably wouldn't be on a registry in the first place), so you either need a skill that another country will give you a work visa for, or you have to work under the table on a tourist visa, which carries its own set of hardships and risks.
So my partially but not totally informed take on it is that it would be difficult, but not impossible, and the world would not be your oyster. You could make it work, but you'd have to be able to tolerate a measure of hardship and uncertainty.
The only exception I could think of would be if you had a skill that was desperately needed in a given country, and that country didn't regard whatever particular crime you were convicted of to be a big deal.