CAsey Anthony

Judicial war over causes of chloroform found in accused murder mom CASEY ANTHONY's car trunk where prosecutors claim toddler corpse may have been stashed.

The debate over admissible evidence continues in the pretrial hearings of Casey Anthony in Orlando, Fla., where she stands accused of murdering her 2 year old daughter Caylee.

Prosecution expert witnesses claim traces of the knock-out drug were present in the car trunk, lending credence to the case they are trying to construct  a case of premeditated murder.

But expert witnesses for the defense introduced a shocking new theory during a recent hearing, WESH-TV reported.

At the Oak Ridge National Laboratory in Tennessee forensic scientists tested the air in Anthony's trunk.  Tests showed it to be saturated with vaporized chloroform.

BUT, the defense claims that the chloroform traces were left by residual amounts in Caylee's bathing suit – with pool chlorine as the culprit.  

"The chemical signature would be definitive," chemist Jeff Flowers said.

Defense counsel contends that items that come in contact with chlorine test positive.

According to legal experts, the prosecution's entire case rides on the chloroform – not chlorine – being present in the car trunk.    

Judge Belvin Perry will rule if this evidence will be admissible —  before the sensational murder trial begins next month.