A New York City officer accused in a broad investigation of ticket-fixing conspired with his wife to use money from his police pension to try to have one of the main witnesses against him murdered, prosecutors in the Bronx charged in an indictment unsealed on Thursday.

The officer, Jose Ramos, 43, and his wife, Wanda Abreu, 39, were led into a courtroom in handcuffs for their arraignment on Thursday afternoon. Both pleaded not guilty to three counts of conspiracy and a single count of criminal solicitation.

“The two defendants have conspired to murder a witness,” a prosecutor, Omer Wiczyk, told Acting Justice Steven Barrett of State Supreme Court. “They were willing to pay a fee, but it was critical to them not to be involved.”

It was the latest and most serious accusation in an investigation that has unsettled police precincts in the Bronx.