The legal practitioner says the relevant provisions in Article 284 of the Constitution states that matters that may bring the office of the President into public ridicule and even matters that subject the whole country to embarrassment are grounds for impeachment.
“I believe with these facts that have come out, it may end up grounding serious charges for impeachment,” said Mr Acheampong.
The Burkinabe contractor, Djibril Kanazoe, gave the President the luxury vehicle as a gift in 2012.
The 2010 Ford Expedition was transported to Accra facilitated by the Ghana Embassy there, Joy FM’s investigative journalist Manasseh Azure has found.
Mr Kanazoe was the contractor who won a controversial $650,000 Ghana Embassy Fence wall contract.
In September 2014, when officials of the Bank of Ghana appeared before the Public Accounts Committee of Parliament (PAC), it emerged that an amount of $656, 246.48 had been spent on the construction of a fence wall over a parcel of land belonging to the Ghana Embassy in Burkina Faso.
PAC ordered the Bank of Ghana to investigate what it termed the “outrageous” cost of the project.
Joy News sources close to the fence wall project say procurement procedures were breached in the award of the contract.
Mr Kanazoe is also the only African contractor who won part of the contract on the Eastern Corridor Road Project, one of the biggest road projects ever to be undertaken in Ghana.
The Presidency has confirmed, through the Communications Minister, Edward Omane-Boamah, that it received the luxury vehicle but insists the gift does not constitute bribery.
Mr Acheampong says so far as the gift was given to Mr Mahama, and not the state, it raises questions.
"There is a clear unconditional acceptance that the vehicle was donated to the President. They did not say the vehicle was donated to Ghana. So that if the President is currently claiming through the Minister of Communications that the vehicle has been given to the Presidency and added to the car pool, under what circumstance? Is it still in the President's name or Ghana? These are the murky questions that come around the whole issue," he said.
Article 284 of the 1992 Constitution states, “A public officer shall not put himself in a position where his personal interest conflicts or is likely to conflict with the performance of the functions of his office.”
This constitutional provision has informed a new bill, Conduct of Public Officers Bill, 2013, presented by Cabinet to Parliament.
According to Section 21 (b), a public officer may not “ accept a gift, favour or an advantage that has the potential to influence the proper discharge of the public officer’s functions or judgment, from a person with whom the public officer comes into contact in relation to the public officer’s functions”.
Mr Acheampong says anyone who feels the President's acceptance of the gift in 2012 constitutes conflict of interest can head the Commission on Human Rights and Administrative Justice (CHRAJ) for the Commission to determine same.
He says once it has been determined by CHRAJ as constituting a conflict of interest, Parliament can be petitioned to impeach the President.