[threevodka]

Evidence is evidence. Witness testimony is evidence, photographs are evidence, video is evidence, dna is evidence. All evidence has credibility, which can be challenged.

Every case is different: witness testimony can be far more credible than photo evidence, dna evidence can be less credible than video evidence.

There is — as far as I know — no legal system in the world that measures the validity of a case based on the amount or type of evidence. You can absolutely be convicted on witness testimony alone in the US. That’s very unlikely but entirely possible under the law.