I didn't find anything specifically on point, but I also ran a search using a free Google legal database based on some hints I got in the paid one. I am going to put a link to the search below and he may want to go through each of those cases to see if they would help.
I think he may want to argue that he needs the identity of the informant, the phone records, and the internal investigation to see if it supports a motion to suppress.
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