Quebec prosecutors dropped some charges against former Liberal minister Nathalie Normandeau, who was being investigated for fraud, corruption and conspiracy.

Normandeau faces breach of trust charges and fraud against the government in relation to the contracts with the Boisbriand water treatment plant.

Her lawyer, Maxime Roy, has maintained that his client did nothing wrong.

The former-deputy premier and minister of municipal affairs in Jean Charest's Liberal government was arrested by UPAC along with six other people including her chief-of-staff on budget day in 2016, as a result of two separate investigations, one into the awarding of government contracts including the water-treatment plant in Boisbriand in 2007.

The other investigation was into politicians who allegedly used their positions to obtain gifts and donations.

The others arrested in the case also saw charges dropped.

Normandeau was the MNA from Bonaventure and an influential minister who served as a Liberal member of the legislature from 1998 to 2011 and held key cabinet positions including municipal affairs, natural resources and Canadian intergovernmental affairs.

Chomedy MNA Guy Ouellette was also arrested by the anti-corruption squad in 2017 but never charged. He was suspected of leaking information about a police investigation and subsequently left the Liberal caucus.

According to political analyst Marlene Jennings, there are grounds for a complaint to be filed at the police ethics board.

"Given their prominent positions, for the police to make all of this public over months and, in a couple of cases, over a couple years, basically staining their reputations, calling into quesiton their integrity, without those charges having actually been seriously evaluated by the director of public prosecutions before moving ahead, to me is a major mistake," said Jennings.