State alleges Rebecca Mercer deliberately set deadly house fire that killed ex-husband and companionMay 18, 2004 | Rockville, Fla.The capital murder trial of Rebecca Ann Mercer, the woman accused of intentionally setting a house fire that killed her ex-husband and his girlfriend, entered its second week Tuesday as prosecutors unveiled what they described as overwhelming forensic evidence tying Mercer to the crime.Mercer, 47, has pleaded not guilty to two counts of First-Degree Murder and one count of First-Degree Arson in connection with the September 14, 2002, blaze that claimed the lives of Daniel Mercer, 46, and Angela Brooks, 39.Represented by Assistant Public Defender Michael Donovan, Mercer has maintained that she was not responsible for starting the fire and that investigators rushed to judgment because of the contentious divorce between the former spouses."This case is built largely on circumstantial evidence and assumptions," Donovan told jurors during opening arguments. "The State has created a story, but a story is not proof beyond a reasonable doubt."Prosecutors strongly disputed that claim.Assistant State Attorney Karen Ellis presented surveillance footage, witness testimony, forensic evidence, and DNA analysis that she argued places Mercer at the victims' residence only minutes before the fire erupted.A state crime laboratory analyst testified Tuesday that DNA recovered from a discarded gasoline container found near the scene matched Mercer's genetic profile. Investigators also discovered traces of gasoline and fire accelerants inside the trunk of Mercer's vehicle after it was seized less than twelve hours following the fire.Crime scene investigators further testified that several items recovered from Mercer's car—including disposable gloves, partially burned clothing, and a lighter—contained residue chemically consistent with the accelerant used to ignite the blaze.Perhaps the most damaging testimony came from a neighbor who told jurors she saw a woman matching Mercer's description arguing with Daniel Mercer outside the residence shortly before flames engulfed the home."I heard yelling," the witness testified. "About fifteen minutes later, I looked outside and the front of the house was on fire."Fire investigators concluded the blaze was intentionally set near the front entrance, preventing the victims from escaping as flames rapidly spread through the residence.Defense attorneys attempted to cast doubt on portions of the forensic evidence, suggesting investigators failed to adequately preserve the crime scene and overlooked alternative suspects. During cross-examination, Donovan repeatedly questioned investigators about gaps in the chain of custody surrounding several pieces of physical evidence.Mercer remained largely expressionless throughout Tuesday's proceedings, occasionally consulting with her attorney while family members of both victims watched silently from the courtroom gallery.If convicted, Mercer could face the death penalty. Prosecutors have indicated they intend to seek capital punishment, arguing the killings were premeditated and especially heinous because the victims were trapped inside the burning home with little chance of escape.The trial is expected to continue through next week, with additional forensic experts and fire investigators scheduled to testify before the defense begins presenting its case.