Jurors in Brittany Norwood’s murder trial will probably not hear about the motive that prosecutors think drove her to kill a co-worker inside a Bethesda yoga store, according to court proceedings Monday.

The jury did hear Monday about blood and DNA evidence tying Norwood to the attack on Jayna Murray — a point that prosecutors drove home by calling forensic experts to the witness stand. William Vosburgh, an expert in blood-spatter analysis, described how Murray — trapped in a rear hallway in the store — was struck repeatedly in the head with a weapon, causing blood to be sprayed on three walls.

“It’s coming off of Jayna?” asked Montgomery County State’s Attorney John McCarthy.

“It’s coming off of Jayna’s head,” Vosburgh said.

Norwood is accused of beating and stabbing Murray the night of March 11 in the Lululemon Athletica store in downtown Bethesda and staging a cover-up.

As for the motive, McCarthy will probably not be able to tell jurors his explanation of why Norwood attacked Murray: that the two quarreled over merchandise Murray thought Norwood had stolen from the store. In court Monday, out of the presence of the jury, and in previous filings, McCarthy laid out this theory:

On the night of March 11, the two women closed the store, cleaned up and prepared to leave. They checked each other’s bags, per store policy, and Murray found a pair of yoga pants in Norwood’s purse. She asked Norwood about them, and Norwood told Murray she had bought them from another store employee, Chioma Nwakibu.

Norwood and Murray then left the store, heading in different directions. Murray called Nwakibu, who said she had not sold the yoga pants to Norwood. Several minutes later, Murray got a call from Norwood, who said she had left her wallet at the store and asked Murray to meet her there so she could get it. Norwood made that call to lure Murray back to the store, McCarthy said. An argument ensued, in which Norwood could be heard saying to Murray: “Tell me what’s going on.” Norwood then attacked Murray.

McCarthy’s problem, legally speaking, was that to tell that account to jurors, he would have had to piece it together from cellphone records and by calling Nwakibu as a witness to recall words spoken to her by Murray — in other words, hearsay, which is often inadmissible in court trials.

“I don’t know how much more hearsay it could be,” Montgomery Circuit Judge Robert Greenberg told McCarthy in court Monday, before the jury was ushered in for the day. “And I am not going to permit it.”

McCarthy had another option for getting the theft allegation into the trial: Norwood’s statements March 18, the day she was arrested. Detectives allowed her brother to come into an interrogation room and left the two alone. An audio-video system picked up their conversation. Norwood acknowledged to her brother that she’d been accused of stealing, McCarthy wrote in court papers filed before the trial.

But in court Monday — out of the presence of the jury — McCarthy said he would not play the video. It was unclear why, and he declined to comment outside the courtroom.

Defense lawyers do not dispute that Norwood killed Murray. They say that she snapped and that it was not premeditated murder. The distinction could make a big difference. In Maryland, premeditated murder carries the possibility of life with no chance for parole. Second-degree murder carries a maximum of 30 years in prison with a chance for release after 15 years.

Earlier in the trial, McCarthy said Norwood inflicted at least 322 injuries to Murray, and forensic examinations suggested she used an array of tools and items from the store — including a hammer, wrench, rope, knife and a metal peg used to hold up merchandise.

On Monday, McCarthy called the blood-spatter expert, Vosburgh, to try to establish that the attack was deliberate and took time. Vosburgh said the blood on the wall indicates that Murray was first struck when she was standing and continued to be struck as she fell to her knees and the floor.

He said that Murray was so low on the floor that the underside of a bookshelf — 21 to 22 inches off the ground — contained blood that had sprayed off Murray’s head as she was struck. McCarthy showed photographs on a large screen of Murray’s body and photographs of blood on the walls.

“This is fairly typical of a severe beating situation,” Vosburgh said.

Under cross-examination, one of Norwood’s attorneys, Doug Wood, tried to show that the attack didn’t last long.

“You’d call it a quick timeline, right?” Wood asked.

“Yes,” Vosburgh said.

Prosecutors also called Erin Farr of the Montgomery police department, who studied DNA in the case. She analyzed a sock and shoe Norwood had been wearing; both contained blood that matched Murray’s DNA.

Farr also tested a rope found in the store. It didn’t contain any blood, but it tested positive for Norwood’s DNA, suggesting that she had handled the rope. Another section of rope was found around Murray’s neck.