However, there are at least two scenarios where Roberts may be called upon to wade into a trial already marked by deep partisan rancor and mutual suspicion. First, if a vote on witnesses or acceptance of claims of executive privilege (or any matter) results in a 50-50 tie, the Chief Justice – and not the Vice President – will be forced to cast a tiebreaking vote.
That's from a far-lefty journal. I don't think many hold this view.
That was then; this is now. The Senate sets the rules, and apparently, at some point, the rule has changed, and the Chief Justice cannot vote. A tie is the same as a fail.
justsecurity.org is part of lawfare.org, and is directly associated with the efforts to undermine conservatives and remove Trump. ANYTHING they say can be dismissed offhand. They are straight propaganda.