What is the Criteria to became a Cyber Expert?

Hi,
If a non computer engineer who run cyber cafe can became police cyber expert ? How can we challenge it because the claims made by that expert is wrong. Is only proving that he is non-IT enginner and non eligible for this case will make wrong evidences null in front of judge or not or we still need to take it further and prove that evidences also wrong or misrepresented ? Can we take any legal action against this expert ?

HI Nudd,
Yes, I think that expert have to be qualified like engineering in computer or mca without it cant say expert
evidence becomes null. Running cyber cafe is not expert at all is just like business man.