Forensic linguists have studied such things as cell-phone contracts and agreements to

1.make criminal identification with 100 percent certainty

2.make a language profile of criminals

3.make language more understandable and accurate at all levels

4.do away with all inequality

1. Make criminal identification with 100 percent certainty.

Explanation:

Linguistic forensics are people trained to listen to the voices of criminals through phone calls or recordings and compare them with the alleged suspects and thus be able to determine with certainty whether or not it is the suspect who triggered the crime.

That is why the registration of the voice was considered an evidence.