Is there like, a committee who decided this? Honestly, I'd never leave it up to Sanders' fanbase whether criticisms against him are okay.
It's less about the acceptability of their criticisms and more about the visibility of their efforts, in my opinion.
It's getting to the point where the most prominent visual of the Sanders campaign is of him being shouted down by black protesters. A lot of posters seem to think that this will reflect poorly on black protesters, but I think it's more like to reflect on Sanders; at this point, he has received the most visible and unrelenting opposition by black interests of any candidate in either major party in this campaign.
The degree of resistance that he receives is, it seems to me, pretty wildly disproportionate to the degree of racism inherent in his policies, as opposed to those of someone like Rand Paul or Ted Cruz, or even one of the other Democratic candidates, both of whom have more pronounced links, however tenuous or ancient, to the "tough on crime" movement of the '80s-00s than does Sanders.
The real threat here is that the most prominent black political force of our time creates a perception of racism around the policies of the most liberal credible candidate in modern US history, and, for whatever reason, completely ignores every other candidate, at least in the sense of the very high profile attention that they've given to Sanders.
