Defense attorney Thomas Connolly charged Monday that investigators’ conspiracy theory in the puzzling case of murdered attorney Robert Wone is based partly on faulty blood testing.

Connolly pointed to some 170 items in the house where Wone was found dead in 2006 that initially tested positive for traces of blood. All 170 items were shipped to the FBI for further testing. Every test came back negative.

“You came to form a belief with these presumptive tests that there was a lot of unaccounted blood,” Connolly said during the cross-examination of a police evidence technician on Monday.

Attorneys for alleged conspirators Joe Price, Dylan Ward and Victor Zaborsky, each charged with covering up Wone’s murder, have complained about investigators’ methods of testing for blood for at least the past year, court records show.

According to a motion to compel discovery filed last May:

In an apparent attempt to identify blood inside of 1509 Swann St., government investigators sprayed a forensic chemical substance known as Ashley’s Reagent throughout the house. The application of the chemical led the investigators to concolude that dozens of spots were ‘presumably positive’ for blood. When tested by the FBI, however, they proved not to be blood at all.

In response to a request about the widespread use of Ashley’s Reagent, [Assistant U.S. Attorney Glenn] Kirschner informed the Defendants that ‘[i]t has been determined that the Ashley’s Reagent was used in a manner not intended by the manufacturer of that product’….

The government accuses the Defendants of knowing more than they have told, and lying to the police, based entirely on the absence of evidence to suggest that an intruder killed Robert Wone. That ‘absence of evidence’ includes no evidence of blood or DNA belonging to Mr. Wone anywhere in the house, except on the bed adjacent to the decedent’s body. As we know now, it may have been the government’s own action that contributed to the ‘absence of evidence.’