He was arrested at the judge's home in Mesa earlier this month.
53-year-old Michael Krause was wanted by authorities out of New York.
Krause appeared in a Maricopa County court after his arrest two weeks ago. Documents show the 53-year-old was indicted by a New York Grand Jury in December, for attempted grand larceny for means of extortion.
The documents show Krause has previous arrests for assault and rape, and is a registered sex offender subject to sex offender notifications.
He was arrested on January 6, at the home of Maricopa County Judge Katherine Cooper who he called his girlfriend.
Prosecutors say the grand larceny case he's indicted for involves him owning a New York woman's domain name and essentially used it to harass.
FOX 10 contacted Judge Cooper's office for comment. Her office sent a statement from the judge saying, "I did not know that Mr. Krause had a felony conviction or any criminal record, for that matter, or that he is a registered sex offender. I learned this information for the first time on Tuesday after his arrest."
Kraus is scheduled to be in court on Monday, February 2, for a fugitive from justice hearing. He denied knowing about the warrant.
We contacted the Commission on Judicial Conduct regarding possible repercussions for the judge. They told us they investigate when a complaint is filed against a judge, but cannot confirm specific complaints or investigations if there are any in this case.