by Joanna Gin and Edward Imwinkelreid. UC Davis Legal Studies Research Paper, available for free download. Like nuclear DNA testing, GC/MS analysis has important limitations. Courts should not assume it is a nearly infallible technique. When GC/MS is used in drug testing, the court must inquire as to the mode of analysis: full scan, selective ion reliance, or selective ion monitoring. When GC/MS is employed to identify ignitable liquids in arson investigations, the court should inquire as to the condition of the sample tested: Has it been subjected to weathering, microbial degradation, or pyrolysis?