A Costa Mesa man accused of killing his ex-girlfriend and business partner pleaded not guilty to a murder charge Friday morning in Orange County Superior Court, according to the court's website.

On July 8, Thomas Michael Wilhelm, 48, drank cherry vodka, took prescription pills and loudly sang a Guns N Roses song before shooting and killing 45-year-old Christine Murray, court documents allege.


FOR THE RECORD:
An earlier version of this story had the incorrect age for Christine Murray.

Wilhelm and Murray allegedly fought over ownership of the lawn sprinkler company that bore his name the day she was killed at the Redwood Avenue home the two shared with Murray's 8-year-old son.

In a transcript of a grand jury indictment the Daily Pilot obtained earlier this week, prosecutors say Wilhelm struggled with drug and alcohol abuse, which led Murray to question his ability to run the business.

Murray had become friends with one of Wilhelm's other ex-girlfriends who had also once been Wilhelm's business partner, the documents say.

Murray sent that woman text messages minutes before she was killed, the documents say. Murray wrote that Wilhelm was "drunk, locked in his room," and that she had told him they'd talk about the business when he was sober.

"Says he doesn't intend to ever be," she reportedly wrote. "Good then I don't need to change your name, you won't need it."

According to the testimony, Murray later texted the former girlfriend that Wilhelm was playing the song "Used to Love Her," which includes the lyrics, "I used to love her but I had to kill her."

Wilhelm allegedly shot Murray through a bathroom door, firing six rounds and hitting her in the chest, neck, arm and thigh. She was pronounced dead at Western Medical Center in Santa Ana.

Wilhelm is due back in court for a pre-trial hearing Feb. 1.

jill.cowan@latimes.com

Twitter: @jillcowan