Special equipment and tools are necessary to detect these types of criminals

Criminals can hide their identity and hop from one network to the next

The police have no jurisdiction over the Internet

Privacy laws are written to protect people from being investigated for these types of crimes

The rule of best evidence

Hearsay

Chain of custody

Evidence safety

It is too difficult to detect prior modifications

It is corroborative evidence

It is not covered under criminal law, but it is covered under civil law

It is primary evidence

When he cannot be present for testimony

When no other physical evidence is available

When he uses it to refresh memory

When requested by the judge to learn the original issues of the investigations

There is no way to capture electrical data reliably

The evidence in computer cases does not follow best evidence directives

These crimes do not always fall into the traditional criminal activity categories

Wiretapping is hard to do legally

Best evidence is the primary evidence used in a trial because it provides the most reliability

Conclusive evidence is refutable and cannot be contradicted

Circumstantial evidence can prove an intermediate fact that can then be used to deduce or assume the existence of another fact

Secondary evidence is not viewed as reliable and strong in proving innocent or guilt (or liability in civil cases) when compared to best evidence