Absolutely. A confidential informer is a citizen who comes forward and says, “I want to help the police but I want to be kept anonymous.” That's an incredibly important part of our justice system, but those witnesses don't testify in court. They're not witnesses but people who provide information, and it allows the police to do an investigation, get a search warrant, get evidence, or find other witnesses who will testify. That preserves the anonymity of those whose safety is in danger while also preserving fair trials.
Respectfully, this provision wouldn't do that.