证据是诉讼法上，用来确定当事人主张为真实的证明。

客观性：有两层含义，一为“在意识之外，不依赖主观意识而存在”，二为“按事实的本来面目考察，不加个人偏见”。 客观并不代表真实，客观偏重于实物证据的属性，而真实偏重于言词证据的属性。 客观并不代表其排斥主观，典型的就是言词证据，言词证据强调的是主客观的结合。

相关性

合法性

The law of evidence encompasses the rules and legal principles that govern the proof of facts in a legal proceeding. These rules determine what evidence must or must not be considered by the trier of fact in reaching its decision and, sometimes, the weight that may be given to that evidence. The law of evidence is also concerned with the quantum (amount), quality, and type of proof needed to prevail in litigation.