thread It's worse than that
She's holding it because the party could lose their majority under the CPS investigation, they'll be better off if the polls prove correct (which they probably will). They will move the shit hitting the fan to the next time they could lose the election, and even if they lose this they can blame it on the next Government.
permalink And I expect that a sound argument is that
a hung parliament/coalition means ineffective representation at Brexit talks, so Brexit becomes even worse than it already is.