I was working for someone recently fired and now they have decided to lie an say I have stolen materials when I didn't, There are no evidence or witnesses whatsoever can they do this.

You need to understand how the criminal system works. If a crime has been committed, the victim of that crime reports it to the police. The police then investigate and determine if there is enough evidence against someone to give it to a prosecutor. The prosecutor then decides if there is enough to prosecute.

So, if your former employer wants, they can certainly report their claims to the police. If there is no evidence the police will probably let the matter drop.

You then may be able to sue the former employer for filing a false police report.