Full disclosure, I'm in a federal department that has been pushing for more open source for a while. This is a great move by the White House. While there are a lot of groups that are trying to push for more openness and release of software, it can often be challenging. A lot of federal groups have been taught over the years to be very risk averse, and open software is viewed by them to be risk. Probably one of the mo…
I'm pretty sure that, assuming you're a government employee, any work you create that would normally be covered by copyright as part of your job is public domain. There's no license legally possible.
Apparently things are a bit more complicated than this, since works created by government employees are in the public domain in the US, but foreign copyrights are still held by the government. Unless the software is released with a FOSS license where applicable, I don't think public domain government code is compatible with other FOSS licenses (which are generally worldwide).
Even if it weren't the case that the US government held full copyrights abroad, it's still something of a problem because some jurisdictions do not have a concept of public domain - this is why the concept CC-0 licensing comes into play (it's public domain with a permissive license fallback).
See 18F's open source policy: https://github.com/18F/open-source-policy/blob/master/policy...