Sinai, who is currently the Deputy Electoral Commissioner operations, was slapped with the three charges by the National Fraud and Anti-Corruption Directorate yesterday.
Just after lunch time on Monday, he was taken to the fraud office at Konedobu, Port Moresby, to be interviewed by detectives.
His arrest follows alleged involvement in foul play during the by-elections for the Madang Open seat.
Sinai was the election manager based in Lae during the National Election. However, he was appointed returning officer for the Madang Open by-election in 2013.