It was an unprecedented set of events in Singapore: a government minister charged with corruption and then hauled to court.

S. Iswaran, the transport minister, was formally accused on Monday of taking bribes including a ride on a private jet and tickets to the musical “Hamilton” and soccer games in Britain. By the time he appeared in court on Thursday and pleaded not guilty, he had resigned from his post.

Singapore has long touted a squeaky clean image and a lack of graft. But in recent months, several scandals have tarnished the governing People’s Action Party’s reputation — and, in effect, the country’s.

Allegations of impropriety involving Mr. Iswaran became public in July. Prime Minister Lee Hsien Loong ordered him to take a leave of absence while the authorities investigated Mr. Iswaran’s dealings involving a billionaire who helped bring the Formula 1 auto race to Singapore. The charges unveiled against him include two counts of corruption and one charge of obstructing justice. He is also facing 24 counts of “obtaining, as a public servant, valuable things” worth more than hundreds of thousands of dollars.

“One can’t deny that this is a body blow to the P.A.P., to the government and to Singapore,” said Eugene Tan, an associate professor of law at Singapore Management University. “This is a system that has always prided itself in high public life standards and incorruptibility. When you have a series of allegations that a minister had compromised himself, that does raise legitimate concerns.”

In addition to Mr. Iswaran’s case, the P.A.P. last year faced questions of impropriety in the real estate dealings of two ministers involving government bungalows, and pertaining to the speaker of Parliament’s extramarital affair with another lawmaker. Although the government found no evidence of wrongdoing or corruption in the real estate matter, the incident raised questions about the privileged positions that ministers have in Singapore at a time of rising living costs.