Does donating money to cover legal fees of Jews who are being charged with crimes which carry a prison term count as pidyon shvuyim? Does it matter if the country is western (US/Canada/UK) or not (Japan/Turkey/etc)?
The concept of modern imprisonment would not fall under the category of pidyon shvuyim, because it does not pose a threat to the captive’s life, which was the case in Chazal’s conception of pidyon shvuyim. This makes a practical difference for the order in which tzedakah should be allocated, in which pidyon shvuyim tops the list. However, it still remains an important mitzvah to help Jews in such dire need, both after their guilt is proven and the more so certainly before, and in particular in regimes where prison sentences are not geared towards rehabilitation and involve sometimes cruel and excessive punishment.
Sources: See Shulchan Aruch, Yoreh De’ah 252:1, which is based on Gemara, Bava Basra 8. Marcheshes (1:43) writes that pidyon shvuyim does not necessarily involve a definite risk to a person’s life, but it must involve at least a possible risk to his life.