The evidence is always going to be important whenever there are cases that are being heard in court. Even in real life, there are some people who would search for evidence first before they do something. Without proper evidence, it will be hard to make assumptions about what truly happened.
There are situations that may seem like we know exactly what has occurred only to realize that things are completely different from what we have expected. It is. The testimony refers to the statement of the witness regarding the case. Hearsay is another term for rumors. Hearsay will not be admissible in court.