SULTAN — Homicide detectives are probing some research a Sultan woman may have done about deadly plants before her former boyfriend turned up dead.

Debra Canady is accused of helping to plan and cover up the beating death of David Grimm. Canady, 46, and her current boyfriend, Brent Starr, 30, were charged Friday in Snohomish County Superior Court with first-degree murder.

Starr is accused of beating Grimm to death with a hammer June 26 while the 49-year-old man slept. Canady later called 911 and told police she found Grimm in his bedroom and he appeared to be dead.

Detectives also are investigating the possibility that there are as many as four life insurance policies taken out on Grimm naming Canady as the beneficiary, Snohomish County ­deputy prosecutor Ed Stemler wrote in charging papers.

The policies may provide a potential motive, Stemler wrote.

Investigators found a text-message conversation the couple believed they’d erased. Police contend it documents the pair’s alleged involvement in the killing, according to court papers.

Grimm and Canady broke up about three months before the killing, but he continued to live in the Sultan house shared by Canady, her mother and daughter.

Canady and Starr allegedly wanted Grimm out of the house.

There may have been a reason Canady didn’t force Grimm to leave.

Detectives found embarrassing photos of a sexual nature when they searched a safe in the home and a briefcase Grimm had in his pickup truck, according to court papers. Investigators believe Grimm may have been keeping the photos as a way to force Canady to allow him to stay in her home.

The photos allegedly depict Canady engaging in bestiality, Stemler wrote.

Reporter Diana Hefley: 425-339-3463 or hefley@heraldnet.com.