I recently got written up for "internet usage" well I asked them to show me where they saw me on the internet ( they haev a program called Ewitness that records literally everything we do). Well I told them I wasn't signing it until I saw the proof. The times they say I was on the internet don't match up.they say I was on @ times when I wasn't @ my desk. Whats going to happen if I don't sign it?
I was told that it still goes in my file but it will be noted that I refused to sign but will still go against me?
Is this true?

Is there anything I can do if these accusations are false?

If you don't sign the warning, then it is most probable that nothing further will happen. Nevertheless, it appears you are an at-will employee (i.e., not a union member nor do you have a contract), therefore your employer could legally terminate you for refusing to sign.

Even absent your signature, you should expect that the warning will become part of your permanent personnel file and be relevant in possible subsequent disciplinary action either of the same, similar and/or different matter.

Does your employer have an HR department. If so, then I would contact them immediately and make you concerns known ... in a calm, professional and cogent manner.

Thanks, I am on that now.
Come to find out they have no proof about what they wrote me up for but it shouldn't remain in my file right?

I am in the process of contacting HR because i was written up for something and no evidence was there, so technically they shouldn't have written me up in the first place, right?

Thanks

Wrong. Your employer is not a court of law. They do not have to have proof of what they believe to be true before they can take action.

If you are able to prove to their satisfaction that their belief is incorrect, it would be nice of them to remove the writeup but no law compells them to do so; nor does any law say they cannot write you up without what you would consider proof.

Therefore, if the employer chooses not to remove the warning for whatever reason, then you should request that you be permitted to file a rebuttal to be attached to the warning.

However, please be advised that there is no law that compels the employer to provide you with such an opportunity.