A search warrant filed Monday in the murder case of Baton Rouge civil rights activist Sadie Roberts-Joseph reveals new details about the police investigation, including that someone poured bleach over her body in an apparent attempt to destroy evidence.

Roberts-Joseph was found dead from suffocation in the trunk of her car earlier this month. Police announced last week the arrest of Ronn Bell, 38, the victim's tenant who was $1,200 behind on rent. Bell's arrest warrant notes his DNA was found on Roberts-Joseph's body.

Detectives later found two empty bleach bottles inside his house.

Police also said video evidence shows him near where her car was found — about 3 miles from her Scotlandville home, which is down the street from the house he was renting. Bell later admitted to detectives that he had been in the location where the car was found, but said he was not inside the vehicle and had not seen Roberts-Joseph for several days before her death.

Bell's attorney, Sara Clarke, filed a motion Friday in which she questioned whether it's possible police illegally seized his hair and planted it on Roberts-Joseph's body just hours before obtaining the arrest warrant. Clarke said her client was not shown a search warrant when officers took hair from his head the day before he was arrested on a first-degree murder count.

Baton Rouge police on Monday filed that search warrant into the court record.

The accompanying affidavit says that after Roberts-Joseph was killed, she was "placed into the trunk of her vehicle, and then had bleach poured over her body." After investigators developed Bell as a suspect, they obtained a search warrant for his house, which led them to two empty bleach bottles in the main bathroom.

Detectives also found "small black fibers" on the bleach bottles, according to the affidavit. The autopsy yielded similar fibers on Roberts-Joseph's body.

The officers requested a search warrant to seize a sample of Bell's hair "to be compared to the fibers located on the victim's body and the fibers located on the empty bleach bottles inside his residence."

The warrant was signed July 15, the day before police announced Bell's first-degree murder arrest. Another search warrant also dated July 15 authorized police to take a sample of Bell's saliva for DNA testing.

Bell's defense attorney had argued in her motion that it was unnecessary for police to obtain hair and saliva because they both contain DNA.

"For what purpose would law enforcement need hair and then saliva, in that order? Saliva alone would be sufficient to compare any and all DNA that allegedly was found," Clarke wrote in the motion. She questioned whether "the hair that was seized from his head by law enforcement on Monday, July 15, 2019, is the hair that was referenced in the arrest warrant affidavit (from July 16, 2019) as being 'found' on the deceased."

East Baton Rouge District Attorney Hillar Moore III said Monday that the hair was requested specifically to be compared to the black fibers found on the body and bleach bottles, not to be used for DNA testing. He said that's why police needed the saliva too.