The executive director of the watchdog group, Transparency Solomon Islands, has no doubt Manasseh Sogavare was dumped as Solomons' prime minister over the anti-corruption legislation he was advocating.
Mr Sogavare was toppled yesterday, losing a vote of no confidence in the 50 seat parliament by 27 to 23.
The MPs who voted for the ouster included a number who had been in Mr Sogavare's cabinet until only recently.
The MPs have denied it was over the anti-corruption bill, but Ruth Liloqula said her organisation and the Solomon Islands general public thought otherwise.
"When they actually tabled the motion of no confidence and all the justification for that it does not ring true for anybody. It was shallow and the counting of numbers to pass the motion of no confidence, and I don't think we are impressed with what's going on."
Solomons police appeal for calm
Meanwhile, police in Solomon Islands have appealed for people to remain calm in the wake of the toppling of Mr Sogavare.
The Solomon Star reported the Police Commissioner Matthew Varley reiterated the independent role of the police and the need to uphold the law at all times.
He said the police would deal sternly with anyone who might be planning to disturb law and order in coming days.
The police chief said police had been deployed around the capital Honiara "to ensure the rule of law is observed and no one takes the law into their own hands".
He appealed to people to report anyone "planning to carry out any illegal activities to take advantage of the current political situation".
"Solomon Islands is a democratic country and the democratic processes must be allowed to take their course in the country," he said.
"Freedom of speech, which is the corner stone of any democracy, must be exercised with a greater responsibility during these times.
"The RSIPF appeals to anyone who may have any information about groups or individuals who might be planning to carry out any illegal activities to take advantage of the current political situation to contact the police on the emergency toll free phone 999," said Mr Varley."