Searching for the evidence.
I myself have tried to get copies of the government's raw data on FST "accuracy."

Anacapa Sciences contracted to do the 1998 San Diego FST validation study. Dr. Jack Stuster, principal scientist at Anacapa Sciences and an author of the study, quickly and cheerfully sent the relevant data set. This was the only FST study for which I have been able to get raw data.

What the data proved about FST inaccuracy is shocking.

NHTSA

All data

A FOIA request to the NHTSA failed to get any FST study raw data.

So I called Washington, DC and spoke with the NHTSA's Chief Counsel's Office—the agency's self described "FOIA experts." Agency lawyers claim all the FST data was lost "when we moved to this new office." The data was also lost, "when we moved to a paperless office." This happened, "a few years ago"—some time after a similar FOIA request was honored, resulting in Dr. Hlastala's 2005 scientific article sharply critical of NHTSA's statistical methods.

Two FST validation study reports originally included raw data about individual drivers. The final report of the 1995 Colorado study originally had an appendix matching driver BACs with officer arrest decisions. It does not give FST scores. The final report of the Florida study originally had an appendix with a "case log," apparently revealing raw data for each driver.

Based on my FOIA request and my discussions with the agency's Chief Counsel's Office, these appendices have been expunged from the reports now released by the NHTSA. The expunged Colorado appendix is available on the web. The expunged Florida appendix is not in any version of the report I have found. IF YOU HAVE THE FLORIDA STUDY, APPENDIX 4, please let me know. FST (at) medmalexperts.com

SCRI

Southern California Research Institute contracted with the NHTSA to do the Florida, Colorado, 1981, and 1977 studies. SCRI raw data seems to be secret. SCRI's executive director, Dr. Dary Fiorentino, answered my emails, but refused to release any raw data. At least I think he did—I was never able to decode his responses to tell whether the data has been lost, or destroyed, or whether it still exists but is secret.

SCRI's executive director even refused to release the "case log" appendix originally included in the Florida study's official final report (a study he worked on), although again his apparent evasiveness left me unsure if the official report SCRI was paid hundreds of thousands of dollars to prepare has been lost, destroyed, or is secret.

Dr. Marcy Burns
All data

Dr. Marcy Burns, principal author of the San Diego, Colorado, Florida, 1981, 1977 studies, refused to release any data. The only response I've yet gotten from her is the green USPS certified mail receipt she signed when my request was delivered.