Federal authorities charged a second judge Wednesday in a slowly unfolding case-fixing scandal in Philadelphia Municipal Court.

Prosecutors say Judge Joseph J. O'Neill lied to FBI agents who were investigating special treatment he gave to a Democratic Party fund-raiser facing a small-claims case in 2011.

The charges were not unexpected. One other judge and the fund-raiser at the heart of the case have pleaded guilty to fraud, and prosecutors had indicated in filings before a state judicial disciplinary court last month that O'Neill would be the next to face indictment. Two other judges have also been accused of ethical violations but have not been criminally charged.

O'Neill appeared unnerved as he pleaded not guilty during an initial hearing in U.S. Magistrate Court. Handcuffed and wearing a rumpled white dress shirt and slacks, he stood out among defendants outfitted in olive prison jumpsuits.

The judge's lawyer, Gregory Pagano, declined to comment on the allegations. He said O'Neill turned himself in Wednesday morning to U.S. marshals.

Like the other Municipal Court judges caught up in the four-year probe, O'Neill faces allegations tied to his relationship with Judge Joseph C. Waters Jr., who was caught on FBI wiretaps attempting to influence several rulings by his colleagues to benefit his friends and donors.

Waters contacted O'Neill twice in 2011 seeking favors for Samuel G. Kuttab, a Democratic fund-raiser who counted mayors and congressmen among his friends. At the time, Kuttab's family property-management company was being sued over a $2,700 debt.

The plaintiff, Montgomery County-based Houdini Lock & Safe Co., said it never received payment on a contract Kuttab signed hiring it to monitor alarms at a warehouse his family owned. When the case came to trial before O'Neill in November of that year, Waters intervened.

"He's a friend of mine, so if you can, take a hard look at it," Waters told O'Neill in a conversation caught on an FBI wiretap and quoted in court filings.

"No problem," O'Neill replied. The judge later ruled in Kuttab's favor.

When Houdini later threatened to appeal O'Neill's ruling, Waters again stepped in and helped broker a settlement. In the end, Kuttab paid Houdini $600 of the $2,700 it said he owed.

When later questioned by FBI agents, O'Neill twice denied that anyone had contacted him before the Houdini case went to trial, according to the indictment unsealed Wednesday. He allegedly told investigators during a September 2012 interview that if someone had asked him to fix a case, he would have punched them in the face.

Waters, who pleaded guilty to mail and wire fraud in 2014, is serving a two-year prison sentence at a federal detention center in Kentucky. Kuttab was sentenced to six months last year.

State judicial authorities suspended O'Neill and another judge accused of doing favors for Waters, Dawn Segal, at the time of Waters' indictment.

Segal has not been criminally charged and her lawyer has said she fully cooperated with FBI agents investigating the case.

A fourth judge - Angeles Roca - has also been accused of ethical violations, including asking Waters to intervene in a tax delinquency case involving her son.

The Pennsylvania Court of Judicial Discipline has yet to rule on whether O'Neill, Segal, or Roca should be permanently removed from the bench.

If convicted of making false statements to the FBI, O'Neill could face up to 10 years in prison.