I don't think any progressive countries impose the death penalty at all, but I suppose this depends on what countries you would include in that category.
Would you consider Canada progressive?
http://en.wikipedia.org/wiki/Kanao_Inouye
I didn't mean it is necessarily like this today, but rather that even progressive countries continued to execute for treason at least partway through their history of progressiveness. It took longer for that piece (death for treason) to die out than most other pieces (like, I dunno, denying women suffrage?). It's sort of an awkward idea to express.
I could start listing, but you should really just peruse this list:
http://en.wikipedia.org/wiki/List_of_people_convicted_of_tre...
...a person has to do one of two things to be a traitor: either levy war or adhere to (form an attachment to, the Supreme Court once said) our enemies, giving them not only aid but also comfort. The two-witness rule has also made treason cases rare in American history."
http://online.wsj.com/article/SB1000142412788732468840457854...
"…Snowden’s disclosures may have helped the nation’s adversaries (though I’m skeptical as to how much), but treason requires more than that. It is not enough to release important national security information and consort with the nation’s rivals. Snowden may be prosecuted one day. Barring significant new disclosures and developments, it won’t be for treason."
http://www.volokh.com/2013/06/19/snowden-did-not-commit-trea...
> Denmark in Russia represents Iceland, so visa applications for Iceland can be submitted at the Visa Application in centres.
Although, technically, it does not state that you cannot use the Icelandic Embassy, I just assumed they did not, since it said 'Denmark in Russia represents Iceland'. I concede I might have been misguided.
http://rusland.um.dk/en/travel-and-residence/menu-1/where-to...