Steven Avery's new attorney, Kathleen Zellner, has said she's looking to science to prove the "Making a Murderer" subject innocent — but she has been pretty quiet about exactly how.
Now we know at least one test that could prove significant.
Zellner is testing Steven's home and property for minute traces of blood using a chemical called luminol, Steven's brother Earl Avery told "Access Hollywood." "They sprayed the whole house," he said.
Luminol glows when it detects the iron found inside red blood cells and remains effective when used at a crime scene years after the crime was committed there.
"The degradation that happens in a blood sample over time doesn't affect the iron. So a luminol test can be used on very old, very dried blood samples and still give a very good positive," criminal justice professor Nathan Lents, who is not involved in the Avery case, told the TV show.
"In fact, it actually gets better over time because some of the agents that would interfere with the signal get degraded, but the iron doesn't," he continued. "Iron doesn't go anywhere."
During Avery's trial, the prosecution alleged that Steven and his then-teen nephew Brendan Dassey tortured and raped photographer Teresa Halbach in Steven's room, and said she was shot in the head in the garage. If all that actually happened, the events probably left traces of blood for luminol to detect — even if the scene was cleaned up.
How does this help Steven? If no blood is detected by the test, then it provides reason to believe that Halbach wasn't killed in his home. If blood is found, then it will need to be tested to try to find out whose it is.
Earl is optimistic about Zellner. "Hopefully she does better than the last two," he said, comparing Zellner to Steven's previous lawyers, Dean Strang and Jerry Buting, who are prominently featured in "Making a Murderer."
"They probably did a good job, but look at where [Steven] is," Earl added.
Steven and Dassey are both serving life sentences for Halbach's murder.
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SEE ALSO: Steven Avery's brother says the convict apologized for naming him in the Teresa Halbach murder
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