Lindsay Lohan in court for hearing on jewelry theft charge

Chris Pizzello/AP

Lindsay Lohan arrived for a preliminary hearing at LAX Courthouse in Los Angeles on April 22.

LOS ANGELES - It's the cleavage defense.

Lindsay Lohan's lawyer argued in court Friday that a jewelry store owner must have seen a diamond necklace on her client because of her "extremely" low-cut top.

Sofia Kaman, owner of Kamofie & Co., claims she didn't initially realize the "Mean Girls" star had on the $2,500 necklace when she walked out of the store in January.

During a testy cross-examination, Lohan defense lawyer Shawn Holley tried to poke holes in that contention.

"Isn't it accurate that her entire chest and neck were visible with what she was wearing?" Holley asked.

"Yes," Kaman said. "I wasn't looking at her chest, but she was in front of me."

"You weren't looking at the glimmering diamond?" Holley asked incredulously.

Lohan is charged with felony grand theft - and possible probation violations - for allegedly swiping the bauble.

During a preliminary hearing in Los Angeles, prosecutors tried to show the troubled actress deliberately left the store with the necklace.

In an attempt to show a pattern, they questioned a store clerk who testified Lohan had tried to leave with a diamond earring four days before the alleged necklace theft.

Lohan arrived to court next to her lawyer, Shawn Chapman Holley. (Chris Pizzello/AP)

Tinelli Comsooksri said LiLo came in Jan. 18, 2011, and tried on 18-carat white gold and diamond earrings with a $1,180 price tag.

Then she returned just one of them.

"What happened to the second earring?" prosecutor Danette Meyers asked.

"It was still in her ear," Comsooksri testified.

She said Lohan turned toward the door to leave.

"I reminded her that she had our earring on," Comsooksri said. "She said, 'Sorry.'"

Prosecutors say that less than a week later, Lohan returned to the store, tried on the necklace and left.

Lohan claims the necklace was loaned to her and the store filed charges to drum up money-making publicity - which Kaman denied.

"Have you ever entered into an agreement she could come into your store take your jewelry and pay for it later?" Meyers asked.

"No," Kaman answered.

She defended her decision to sell surveillance video of Lohan to the media, and claimed her publicist created a pay-per-view website against her wishes.

"We told him we were strongly opposed to that, that we didn't condone or authorize it," she said. "He said too bad."

Holley hammered away on that point.

"You would agree this incident has given your store a lot of publicity?" she asked.

"Yes," Kaman admitted.

"Celebrity sells, right?" Holley asked.

"It can," the merchant responded.

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