I believe she is guilty.

The whole scene of having a shower despite seeing blood around is not action of a sane person. Either she is mentally unstable or a monster.

She know more than what she is disclosing.

And how stupid can Italian Police & courts be, acquitting her after 4 yrs and then bringing her to trail again.

In the end she is getting so much publicity for her stunts and poor Meridith's parents must be dying everyday.