A former NYPD officer on Thursday pleaded guilty to charges stemming from his involvement in a drug trafficking scheme while serving on the force. Andrew Nguyen, 42, was charged with bribery, narcotics trafficking conspiracy, using a firearm to further drug trafficking, fraud and robbery last fall. Nguyen entered a guilty plea to three of the indictment’s eight counts — bribery and narcotics distribution conspiracy, and a firearm charge — before U.S. District Judge Analisa Torres Thursday. The maximum sentence for the crimes Nguyen pleaded guilty to is life in prison. Beyond the crimes Nguyen pleaded guilty to, charging papers allege wire fraud, robbery and an attempt to possess cocaine with the intent to distribute it.