David Hartley Update: Wife Tiffany Says She'll Take Lie Detector Test if Necessary

ZAPATA, Texas (CBS/AP) As search teams from the U.S. and Mexico continue to comb a lake on the U.S.-Mexico border to find the body of missing American tourist David Hartley, his wife Tiffany continues to fend off speculation that her version of events might not be true.

PICTURES: Tiffany and David Hartley

Now she says she's willing to take a lie detector test to prove things happened just as she says they did.

Tiffany Hartley said her husband, David, was shot to death by Mexican pirates chasing them on speedboats across Falcon Lake on Sept. 30 as they returned on jet skis from a trip to photograph a historic Mexican church. Neither his body nor the jet ski has been recovered.

It's a tale of violence that isn't as far-fetched as it might have been a few years ago, as violence from Mexico's drug war continues to bleed over into the U.S.

Tiffany has now told CNN that she welcomes a lie detector test if "that's what the authorities think I need to do," to dispel the rumors and put the focus back on finding her husband.

"I know what I know," she told the cable news channel. "God knows the truth. And other than that, it almost doesn't really matter to me, because I know what happened that day."

David's family is backing Tiffany. David's mother said Tuesday that the speculation that her daughter-in-law was anything but a victim was "insane," according to CNN.

Meanwhile, the search has reportedly intensified, with people on speedboats, helicopters and all-terrain vehicles searching for Hartley. U.S. officials said threats of an ambush from drug gangs temporarily thwarted efforts.

David's friends and supporters plan to gather for a rally in Denver outside the Mexican consulate at 1 p.m. Friday to bring attention to the case. The group plans to call on the Mexican government to do more to find the American's body.

COMPLETE COVERAGE OF FALCON LAKE SHOOTING ON CRIMESIDER

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