"If you shake the public's trust it's hard to get that back," Nassau County District Attorney Kathleen Rice said.
Nassau county DA Kathleen Rice is now expressing her concerns over what many are calling a prosecutors worst nightmare.
The Nassau County police crime lab is under fire and her office is now forced to retest thousands of drug cases over a three year period.
"For me to be having to take these steps is very disturbing," Rice said.
The first sign of problems came back in December when the crime lab at police headquarters was placed on probation calling into question evidence analyzed at the lab dating back to 2007.
A national organization found 15 serious failures to comply with storing and testing procedures.
The violations included unsecured storage of evidence and an uncalibrated instrument used to determine alcohol content.
So far six of nine drug related cases have shown error in testing, and last week the drug chemistry section of the county's crime lab was shut down.
Defense lawyers believe this is just the tip if the iceberg.
Brian Griffin is one of many attorneys asking for his client's conviction to be set aside.
In some cases, actual prisoners could be set free.
Rice's plan to prevent that includes retesting by an outside consultant.
It will include all felonies, which is some 2,700 samples.
She also wants to retest a 10% random sample from each technician's caseload.
"You are talking about taking away peoples freedom, you better do it right and get it right and that's not a lot to ask," Griffin said.