Politifact:

There’s little disagreement that the convention was chaotic. PolitiFact Nevada was at the convention and saw it firsthand. But does the Sanders campaign’s complaints have merit?

[...]

Our ruling

Sanders campaign manager Jeff Weaver said Nevada Democratic Party leaders "hijacked the process on the floor" of the state convention "ignoring the regular procedure and ramming through what they wanted to do."

Caucuses and delegate math can be incredibly confusing, and the arcane party structures don’t reflect how most people assume presidential selection works.

But the howls of unfairness and corruption by the Sanders campaign during Nevada’s state Democratic Convention can’t change the simple fact that Clinton’s supporters simply turned out in larger numbers and helped her solidify her delegate lead in Nevada.

There’s no clear evidence the state party "hijacked" the process or ignored "regular procedure."

We rate this claim False.


FWIW.

Cheers,
Scott.