What is one method to prove the reliability of a criminal informant?

Demonstrating that the informant provided reliable information in the past is a key method of proving their reliability. Reliability often hinges on a history of accurate and actionable information that an informant has provided, which can be corroborated by law enforcement activities resulting from those tips. When an informant has a track record of giving credible information that leads to arrests, successful investigations, or valuable insights, it establishes a level of trustworthiness.

This method is particularly important because it not only assesses the informant's credibility but also informs law enforcement of the accuracy of the informant's previous claims. In the context of the legal system, this historical reliability can be significant when seeking warrants or presenting information in court, as it can substantiate the informant's value to ongoing investigations.

The other options do not effectively establish reliability in the same way. A criminal record does not necessarily correlate with an informant's ability to provide good information. Revealing an informant's identity can compromise their safety and the integrity of the information provided, while contacting other informants may provide different perspectives but does not directly link to the specific reliability of the informant in question.