COLUMBIA, Mo. -- An appeals panel has overturned the involuntary manslaughter conviction of a central Missouri woman whose lawyer claimed the woman had been drugged before a 2012 crash that killed a 35-year-old man.

Kelli Smith was convicted Dec. 12, 2014, and sentenced to five years in prison for the death of Thomas Sullivan II, who was killed in the wrong-way crash on Interstate 70 in Montgomery County.

In a unanimous decision Tuesday, the Eastern District Court of Appeals in St. Louis threw out Smith's conviction and five-year sentence and said jurors should have been given better instructions on how to consider Smith's blood-alcohol content, The St. Louis Post-Dispatch reported.

The appeals panel said if jurors had received proper instructions, they might have given greater weight to circumstantial evidence raised by the defense. The opinion notes the jury asked several times for a better definition of "under the influence" and "intoxicated condition."

Smith's lawyer, Jennifer Bukowsky, believes someone gave Smith a date-rape drug, then sexually assaulted her and contends if Smith's intoxication was involuntary, Smith could not be held criminally negligent.

"The jury has to look at whether her actions were reasonable under the circumstances," Bukowsky said. "Kelli would not have been behind the wheel going the wrong way on Highway 70 in Montgomery County had she not been forcibly raped and/or involuntarily drugged in Boone County that night."

Nanci Gonder, spokeswoman for the state attorney general's office, which helped prosecute the case and handled the appeal, said in an email Wednesday the attorney general's office is reviewing the ruling. Prosecutors have 15 days to decide whether to fight the ruling.

Montgomery County Prosecuting Attorney Nathan Carroz indicated Tuesday his office would continue to press the case but declined additional comment.

Information from: St. Louis Post-Dispatch, http://www.stltoday.com