"Our Confidential Informant, Fuzzy Dunlop".

Two cops on The Wire do this, and basically register a tennis ball, hence the name, as their CI - https://www.youtube.com/watch?v=9GJa1_u-VLE

Search warrants are usually public record after they are unsealed. If they aren't included in evidence its a Brady violation and if caught the case is essentially dead. If the defense sees that the search warrant was given or executed first, they probably have a very strong argument that all the evidence is tainted. Parallel construction doesn't work very well when proof of tainted evidence is publicly available.