Assuming that the RX is correctly read and entered into the computer, then mistakes, if proper care is taken when reading NDC numbers, could, in THEORY (theory being the key word), be almost completely avoided. Unfortunately, mistakes do happen due to human error. Various machines, such as the scriptpro actually COMPLETLEY fill and lable the bottle. Of course, not reading/entering the script into the computer is almost a guaranteed mistake leaving the pharmacy.
Pharmacies do provide insurance coverage for their pharmacists, though many pharmacists purchase their own malpractice insurance in addition to the coverage the pharmacies provide. Keep in mind that pharmacists are responsible not only for their mistakes but also those of techs and students PLUS physician errors. It sucks, but pharmacists have (successfully) been sued for correctly filling a script containing an error due to the MD/DO/DDS/NP/PA making a mistake. This is one of the many reasons that pharmacy school is so rigorous. While many people, including myself, have often stated that pharmacy school is "overkill" for retail pharmacists, the fact still remains that pharmacists must have extensive training to catch physician medication errors.
Jason