The Election Commission (EC) is set to investigate whether Senator Keskamol Pleansamai has a genuine PhD from California University.
If she does not, it could result in her facing up to 10 years in prison and/or a fine of up to 200,000 baht.
It was reported on Wednesday that the EC has accepted two complaints requesting an investigation into Dr Keskamol's educational background.
This was to determine whether her claim that she was a professor who graduated from California University with a PhD was a deception to win votes and a violation of Section 77 of the 2018 Senate election law.
The complaints were accepted on July 1 and July 5, before Dr Keskamol was declared a senator last week.
According to a source, the EC decided to acknowledge her senatorial position despite the fact the two complaints against her had been approved, because the law does not state a minimum educational degree level which senatorial candidates are required to have.
However, with the complaints having been accepted by the election agency, it will investigate Dr Keskamol.
Under Section 77 of the Senate election law, anyone forcing, influencing or deceitfully persuading others to vote or not vote for a candidate faces a jail term of one to 10 years and/or a 20,000 to 200,000 baht fine. Their voting rights will also be suspended for 20 years.
Meanwhile, the National Institute of Development Administration (Nida) said Dr Keskamol did not graduate from Nida with a doctoral degree, nor is she pursuing one at the institute.
In one social media post, she included the hashtag "#Nida" and said she was attending a class for a doctoral dissertation presentation, leading people to believe that she was a Nida student.
Several news outlets have also reported that Dr Keskamol graduated from Maejo University in Chiang Mai with a PhD in resource management and development.
Koblap Areesrisom, who is in charge of that doctoral programme at Maejo University's Faculty of Agricultural Production, confirmed Dr Keskamol registered for the three-year programme and is now a second-year student.
He said he had previously asked Dr Keskamol to make it clear that she is still pursuing the degree.
Dr Keskamol has since removed the PhD abbreviation after her name on her social media page.
Dr Keskamol, 45, was the senatorial candidate who gained most votes in the final national round of Senate voting on June 26.