The Illinois city that arrested a local man for parodying its mayor on Twitter said Monday that the prankster's detainment wasn't "unreasonable."

The arrest of Jonathan Daniel by Peoria authorities in April made national headlines, and the 29-year-old cook sued in federal court, claiming civil rights violations.

In its first response to the lawsuit, the city of Peoria's and Mayor Jim Ardis' attorney told Ars that the mayor and city officials believed Daniel was breaching an Illinois law making it illegal to impersonate a public official. The mayor's attorney said city officials got a judge to issue warrants from Twitter and Comcast to track down Daniel. In short, they were just following the law.

"We took every step in accordance with the law. They appropriately went to the court to obtain warrants. The court reviewed the statute and evidence and made a determination," attorney James Sotos said in a telephone interview. "In the end, that's a judge's determination to issue a warrant or not. It's not unreasonable that a person would look at that statute to see if there was a violation."

Further Reading How a mayor’s quest to unmask a foul-mouthed Twitter user blew up in his face

Peoria's official court response is here (PDF).

Daniel's suit, brought by the American Civil Liberties Union, claims, "Defendants embarked on a plan to shut down the account and identify and punish its creator in violation of his constitutional rights. As part of Defendants plan, Peoria Police Department officers searched Mr. Daniel’s residence, seized his personal property, reviewed personal information on Mr. Daniel’s electronic devices and in his mail, and arrested, detained, and interrogated Mr. Daniel purportedly for the crime of false personation of a public official."

The ACLU also charged that the law required "an intent to deceive the public that the impersonator is acting in the official capacity of a public official."

Ed Yonhka, an ACLU spokesman, mocked Peoria's response. "The general nature of their responses is that nothing wrong or afoul happened here. The notion that it is not an infringement and abuse of government power and infringement of First Amendment rights to engage in parody is something we disagree with."

Twitter suspended the @peoriamayor handle after the city threatened a lawsuit against the micro-blogging site.

The April police raid was set in motion after the mayor told police that he was upset over being falsely portrayed as a drug abuser, according to court documents. The raid resulted in marijuana drug-possession charges against Daniel's roommate, and charges are pending.

According to a search warrant application, Ardis was concerned that the tweets in the account impersonating him implied that the mayor "utilizes illegal drugs, associates with prostitutes, and utilized offensive inappropriate language."

One tweet the mayor complained to the authorities about read: "...Who stole my crackpipe?"

Another tweet mentioned in an application for the search warrant: "I'm up all night woke up with pussy on my breath and bloodshot eyes and we got people talking bout live tweeting? Let me do my job u do urs." Still another tweet said, "If you don't like Peoria and u wanna sit here and bitch about den leave."

A picture on the account, according to the warrant, was of a "hand holding a razor blade which was separating a white powdery substance."

Peoria Police Chief Steve Settingsgaard, who has subsequently resigned but is named in the suit, said in the immediate aftermath of the raid that the department was investigating a misdemeanor charge of impersonating a public official, which carries a maximum one-year jail term and $2,500 fine.