I haven't been in Politics.SE for long, but I noticed that some questions ar quite short. As an example, one can see the following

• Why are some politicians saying the Iran Nuclear deal is bad?
• Why don't political parties support independent candidates to the extreme of their opponent to split the opposition vote?
• Why does China think that they shouldn't follow the western model of democracy?

they are usually based on the approach: I head someone, somewhere say something. Is that true?

In general, this is not necessarily bad, but as there are no reference at all, it seems the OP did not make the slightliest effort in xir question. I know that on H:SE some users are quite strongly opposed to such question, as illustrated here.

My question is thus: shouldn't we have a policy to, at least, downvote questions based on complete lack of reference?

If the OP does not make some effort in asking a question, why should I make it to answer it? And furthermore ensuring good questions would improve the overall quality of the site.