How to obtain evidence when being blackmailed?

Legal analysis: Keep images and voice information containing blackmail content, such as telephone recording, audio recording, video recording, short message, e-mail, etc. Find an insider to provide witness testimony; Take photos of the injured part in time, and keep photos and injury tools. Provide medical records, diagnosis certificates and medical bills for physical injuries. But what needs to be proved in the whole evidence is that the other party used threats and coercion to ask for property.

Legal basis: Article 50 of the Criminal Procedure Law of People's Republic of China (PRC), all materials that can be used to prove the facts of a case are evidence.

Evidence includes:

(1) Physical evidence;

(2) Documentary evidence;

(3) Testimony of witnesses;

(4) the victim's statement;

(5) confessions and excuses of criminal suspects and defendants;

(6) Appraisal opinions;

(7) Records of the inquest, inspection, appraisal, investigation and experiment;

(8) Audio-visual materials and electronic data.

The evidence must be verified before it can be used as the basis for finalizing the case.