A New York City private investigator who was convicted of hiring hackers to assist in his work now fears that his former clients will retaliate after it emerged that he cooperated with authorities.

In a bid to avoid prison time, Eric Saldarriaga recorded phone calls with one of the hackers he hired at the behest of authorities.

He began to fear his safety and that of his family could be jeopardized if evidence of his collaboration went public. Prior to sentencing, Saldarriaga wrote to the judge to express concerns that details of his cooperation had been leaked to the press, according to the New York Times.

Most of the references to his collaborations were redacted from court filings but the judge eventually had them unsealed, ruling to keep private only specific names of clients against whom Saldarriaga provided evidence.