A Northern California teacher who made national headlines last year after being accused of teaching her second-grade class while drunk will not face criminal charges in connection to the incident following a monthslong investigation, prosecutors said Monday.

Sutter County deputies were called Oct. 2 to Nuestro Elementary School in Live Oak after a caller reported a Yuba City woman drove under the influence to school and began teaching students. She had a blood alcohol level of about 0.20% more than two hours after her arrest, said Sutter County District Attorney Jennifer Dupre in an email. California’s legal limit is 0.08%.

The 57-year-old woman was arrested on suspicion of driving under the influence and child endangerment, The Sacramento Bee reported at the time.

But a subsequent investigation could not substantiate that the 57-year-old woman drove to school while drunk; she may have started drinking “only after arriving there,” Sutter County prosecutors said Monday in a news release.

There was also not enough evidence to prove the child endangerment charge because “there was no specific information indicating that the children in (the teacher’s) class were placed in a position where their persons or health were endangered,” Dupre wrote in the news release.

“The mere potential that a situation could arise is insufficient to meet the requirements under the law,” Dupre continued.

“While the District Attorney’s Office agrees that it is highly inappropriate to teach while intoxicated, it is, unfortunately, not illegal.”

It was unclear whether the woman is still employed by Nuestro Elementary School. Campus officials did not immediately respond to requests for comment.

School administrators at the time of the arrest said they were limited in the information they could disclose regarding a personnel matter. But Bal Dhillon, the school’s principal, said in a letter to parents that a long-term substitute would be teaching the students.

The teacher’s name was no longer listed on Nuestro Elementary School’s online staff directory as of Monday.