Conversation so far:
who is the head of the dnc now
Thomas Edward Perez has been the Chair of the Democratic National Committee since February 2017.
Who was Tom Perez's predecessor as chair of the Democratic National Committee?
Donna Brazile briefly served as the interim chair of the Democratic National Committee in spring 2011, and again from July 2016 to February 2017.
What does the Democratic National Committee do?
The Democratic National Committee is responsible for articulating and promoting the Democratic platform and coordinating party organizational activity.
When was the Democratic National Committee formed?
The Democratic Party's national committee has existed since 1848.

Question: Have there been controversies?
Self-contained rewrite: Have there been controversies about the Democratic National Committee?