Negative Evasion?...huh?!?

Forgive me, but I don't understand how negative evasion works. To my knowledge evasion can't even get that high. (-32 for Palpatine's lead for those sleeping under rocks) So past the zero and into the negative...what happens?...

I understand -5 evasion, even -15....not -32....this is way past Old Ben's/Dooku's lead ability...

Dodge chance cannot be increased to my knowledge. I'm at a loss here people...