The ability to keep U.S. airports and travelers safe is again in the glare of the national spotlight as the Transportation Security Administration begins a new round of tests on X-ray scanners amid concerns about radiation.
Lawmakers and critics have questions about how well they actually work and whether the current system leads to a violation of personal privacy for many passengers.
Lawmakers on Capitol Hill held fresh hearings on the scanners on Wednesday.
"The privacy issues here are enormous. The Fourth Amendment issues are enormous. There's the harm we can see about these devices, and there's the harm we can't," testified Marc Rotenberg of the Electronic Privacy Information Center.
Alaska State Representative Sharon Cissna is a cancer survivor who's prothesis has been detected as an anomaly by the X-ray scanners.
"I fit that profile that instantly is going to have the full, very invasive hand search," she told the committee. "I think it is absolutely an assault."
After a dispute over whether they would be forced to testify with their critics TSA officials did answer questions, including current concerns about travelers being exposed to radiation.
"Machines are tested repeatedly to show how safe They are," said the TSA's Robin Kane.
The TSA also defended its current security methods.
Still, as the agency looks to spend millions on more of the controversial scanners some lawmakers argue the norm right now is simply not good enough.