Mr Chakma resigned as a minister and quit Congress in August 2017.
Mizoram's lone BJP MLA Buddha Dhan Chakma, who has been sentenced to a year in jail along with 12 others in a corruption case, said he has been falsely implicated so that his political career is maligned.
Mr Chakma, who is out on an interim bail to appeal the verdict in a higher court, said he had returned the money for which he was convicted, a year before the criminal case was registered against him.
"In spite of clearing our pay advances, the case's investigating officer charge-sheeted us. Is it not like double punishment for a single case? This is nothing but a conspiracy against us to malign our political images, especially me and Buddha Lila Chakma," he told a press conference in Aizawl on Wednesday.
A special court on Monday sentenced the legislator and five members of Chakma Autonomous District Council (CADC), including its Chief Executive Member (CEM) Buddha Lila Chakma of ruling MNF, for misappropriating funds of Rs 1.37 crore earmarked for development, between 2013 and 2018. Seven former members of the district council were also among the convicts. They drew the amount as pay advances.
The BJP MLA claimed that doling out advance salaries was a regular practice in the council as the then Congress government in the state used to release funds in instalments every four months in a fiscal.
The advance salaries were used for meeting the petty demands of the common people, and the funds were returned immediately once the monthly salaries were received, he said.
The whole process was done in good faith and mutual understanding as no political influence or coercion was put on the executive secretaries, who released the advances, Mr Chakma claimed.
Alleging that the executive secretaries might have improperly maintained the account and siphoned some money out of such recoveries, he said that they came to know about their liabilities only in July 2017.
"We immediately refunded all our pay advances and liabilities clearance certificates were issued to us," he said, adding that the executive secretaries should be made the "prime accused".
Mr Chakma had successfully contested the CADC polls in April 2013 for the second consecutive term on a Congress ticket and was the CEM until November that year, when he was elected to the state assembly and made a minister in the then Lal Thanhawla-led Congress government.
He resigned as a minister and quit Congress in August 2017.
Soon after his resignation, he joined the BJP and successfully contested the state assembly polls in 2018 to become the first-ever BJP legislator in the state.
Mr Chakma said that he would challenge the judgement at the Gauhati High Court within 15 days, and was confident of winning the case.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)