In his book, Judge Sam Amirante, who was John Wayne Gacy's defense attorney, wrote that sodium amytal was used on Gacy. Amirante said in an interview that Gacy's "personality was so strong that he was actually fighting off" the drug. Many accused Gacy of lying about taking the test.
There have been other cases where "truth serum" was allegedly administered and ruled inadmissible in court.
Experts say that one of the issues with using the drug is that it's very difficult for questions not to be suggestive and lowered inhibitions can lead to true as well as false information.
"Understanding of memory has shifted a lot over the years," Winter said. "Memories are really volatile and if you use a technology like drugs or hypnosis, you can get information that's valid, but along with it you get a lot of information that isn't, that's just a response either to something suggestive in how you're asking the question or else just something random that you have no ability to even identify."
"You can't tell the difference between the real stuff and the fabricated stuff," she said.
Despite doubts over the technique's acceptability, Winter understands the intrigue with the idea.
"It's a very seductive idea and it's something that people keep coming back to," Winter said. "We've had it for almost 100 years."
"The idea that the truth about what a person is like or the truth about what they did is just sitting inside their body waiting to be almost surgically extracted...it is just so enticing if you desperately need that information," she added. "So I think we keep coming back to it, but then we also keep rejecting it."