Both parties to the trial must be treated equally.
Equality means that both parties must be given an opportunity to present their case under equal conditions. No party should be put in a substantially worse position than the other.
example If your opponent is allowed to comment on certain evidence at the trial, but you are not, it is likely to be a violation of the principle of equality.
Equal, not the same
The principle of equality does not require that the circumstances of both parties be absolutely the same.
example If your opponent is represented by a group of expensive lawyers, the court is not obliged to grant you the same number of lawyers. Instead, the court must give you equal time and opportunity to present your arguments.
There are many aspects of a trial where the equality of both parties is very important. For example, both parties must be able to present their evidence, challenge the evidence of the other party and present their arguments to the court. This also includes the right to know and access evidence that is given to the court by the opponent. This is important to allow one to prepare one’s commentaries about the evidence or to challenge it.
However, when presenting evidence to the court you should remember that only the evidence and witnesses that the court considers relevant will be accepted. Therefore a court’s refusal to accept evidence if it does not relate to the subject matter of the case will not violate the equality of parties.