I think they did the undercover buying phase before the election because of the notoriety of the LSU suspensions. The St Tammany Sheriffs officers I know are all LSU fans...and they don't like illegal drugs being sold in the parish. I'm sure the sting operation was because of what happened at LSU. I'll ask around.
When it comes to DS confirmation tests, they (the labs) utilize GC/MS for confirmatory testing. The mass spec identifies the chemical structure and mass of the molecules to identify them. The odds of a drug being a false positive by GC/MS is negligible. Of all the challenges to positive DS results that I have seen, I have never seen one come back as a negative after being a lab positive by GC/MS. Therefore, I am confident in stating no false positives because once a DS is positive by a GC screening test, it is rerun on GC/MS to confirm the result.
I just thought that people might want to see what the discussion was the first time around. I thought it was interesting as a an ancillary discussion.