I'm going to spy on my wife after she lied to me
Why you would spy on your wife after she lied to you?
I want to prove that she is lying.
I understand that you feel betrayed by your wife's lies, but spying on her is just as dishonest. Confront your wife directly and leave the subterfuge alone.
We're not talking about lies. She sees other guys and lying about it to me, it's okay right?
Spying is not going to help your relationship. If you really want to know then you need to confront her about it. If she continues to lie and you feel that you can not trust her than maybe the issue in the relationship is trust in general.