01/24/2012 04:52 pm ET

Joran Van Der Sloot Appeals 28-Year Murder Sentence

Just when you thought you had heard the last from Joran van der Sloot, the convicted killer of a young Peruvian woman and the prime suspect in the disappearance of a U.S. citizen, the Dutchman is making headlines once again.

On Monday, van der Sloot's lawyer, Luis Jimenez, filed a motion to reduce his client's prison sentence.

"I am questioning the content of the sentence and asking for a reduction of the years [of the sentence]," Jimenez told El Comercio.

On Jan. 13, Van der Sloot was sentenced to 28 years in prison, for the murder of Stephany Flores.

Jimenez said he has made the request because the three judges who sentenced Van der Sloot did not take into account his client's cooperation with police.

"He was not captured in Chile, he turned himself in," the attorney said.

Jimenez's statement about van der Sloot's arrest is in direct contrast to how Chilean police had described taking him into custody on June 3, 2010. Officials then said Van der Sloot was traveling near the Chilean-Peru border when he was apprehended and taken to a police station in Santiago. No mention was made of surrender.

PHOTOS: JORAN VAN DER SLOOT (Article Continues Below)

Natalee Holloway

Peruvian police had been seeking van der Sloot in connection with the slaying of Flores, who was found stabbed to death in his Lima hotel room on June 2, 2010. Police in Peru say Flores, 21, was killed on May 30, the five-year anniversary of the disappearance of Natalee Holloway, an 18-year-old from Mountain Brook, Ala., who vanished while on a trip to Aruba. She was last seen leaving an Oranjestad nightclub with van der Sloot, then a 17-year-old Dutch honors student living in Aruba. Her body has never been found.

After his arrest in Chili, van der Sloot had allegedly insisted he did not kill Flores, Chilean police said.

Van der Sloot's attorney now claims his client cooperated by giving police a confession.

"[He] gave details of how he had committed the crime," Jimenez told El Comercio.

The validity of Jimenez's claim is somewhat questionable.

After van der Sloot was arrested and transported back to Peru, authorities did announce that the Dutchman had confessed to the killing. "I did not want to do it," van der Sloot allegedly said about the attack.

However, in the weeks following the alleged confession, van der Sloot filed a complaint against investigators in Peru, claiming he was arrested without a warrant and was not provided with an official translator, which he said caused confusion during questioning.

"All this with the intention of pressuring me to accuse [myself] of homicide," the Dutch native said in the complaint.

Van der Sloot also told a journalist from Dutch newspaper De Telegraaf that police "tricked" him into admitting his guilt.

"I was scared and confused during the interrogation and wanted to leave," van der Sloot said. "In my blind panic, I signed everything but didn't know what it said."

According to El Comercio, the court is expected to rule on the latest motion in the case soon. Meanwhile, van der Sloot remains imprisoned at Piedras Gordas prison in Ancon.