On most Fridays and Saturdays in Perugia, Raffaele Sollecito walks into the courtroom wearing a pastel shirt and a sheepish grin. The enigmatic “former boyfriend” of superstar murder suspect Amanda Knox always glances shyly at the cameras and hugs his lawyers. He looks young and studious, like the boy next door.

The two defendants ride in separate compartments of the same police wagon from nearby Capanne prison but enter the courtroom separately, flanked by armed guards. Sollecito watches Knox intently, trying to catch her gaze like a schoolboy with a crush before settling down quickly in a puffy chair directly in front of the judge. She smiles back coyly before the lawyers step between them. In a letter to Sollecito last February, Knox wrote "we got to exchange a few more glances than usual, though I have to admit I’m not good at reading the subtle messages that one passes through the features of the face."

During his original taped deposition, which he has not retracted, Sollecito said he did not know if Knox spent the night of November 1 with him.

In stark contrast to his co-defendant, Sollecito clearly does not revel in his notoriety. He acts nervous and uncomfortable in the spotlight of this epic trial. While Knox spends her days in court with the confidence of an Oscar winner, Sollecito instead sulks with the humility of a murder suspect.

The two are accused of sexually assaulting and murdering Knox’s British roommate, Meredith Kercher, in November 2007. Under the prosecution’s scenario, Sollecito held back Kercher’s arms while Ivory Coast native Rudy Guede, already convicted for his part in the murder, sexually assaulted her and Knox slit her throat with a knife. Sollecito’s DNA has been identified on the tiny metal clasp of the bra that was cut from Kercher’s body after she was murdered. The jury has heard that a knife with Knox’s DNA on the handle and Kercher’s on the blade was found in his kitchen. Expert witnesses for the prosecution have also testified that a bare footprint in Kercher’s blood found on a blue bathmat next to the crime scene matches Sollecito's.

“I have nothing to do with this situation. I am not a violent person and it has never entered my mind to kill anyone,” he told the court last February, near tears. “Anyone who knows me will tell you I wouldn't hurt a fly.”

The 25 year-old information-technology graduate, who finished his degree during his 19 months of incarceration, spends his time in court taking notes, studying his lawyers’ dossier and eyeing Knox. Last month, he helped co-prosecutor Manuela Comodi fix her computer so she could play the crime-scene footage she was using to make the case against him. When he has chosen to address the court—as defendants are allowed to do in Italy—he reads softly from a handwritten script. "I don't know why I'm in this situation,” he said the last time he made a statement. “I regard myself as the victim of a judicial error."

But if he is convicted, it might be because of an error of judgment. He is not scheduled to testify in the trial, although he faces the same possible life sentence as Knox. His lawyers have not explicitly ruled it out, but they say there is little chance he will take the stand. For one thing, his testimony would be the most damning to Knox so far because he cannot corroborate her alibi for the night of the murder. During his original taped deposition, which he has not retracted, he said he did not know if Knox spent the night of November 1 with him, as she claims.

On Friday, Sollecito's father Francesco, a well-connected doctor in Puglia, testified that he was his son's "confidant" and that they spoke daily, with Raffaele sharing the most intimate details of his life. Sollecito had told his father about the budding relationship with Knox, and the doctor testified that they were at the beginning of a "beautiful love story" when Kercher was killed. He also told the court that he had once received a letter from the local police in Bari about his son's drug habit, and that his son collected knives and almost always carried one in his pocket. "It was a habit he had since he was very young," the elder Sollecito said. "I had told him not to carry a knife around."

Dr. Sollecito added that he believed the police had bungled the investigation. "Some very big mistakes have been made," he said. "My son is innocent." Earlier, in an interview on Italian TV, he said of Knox, “She has ruined my son's life. I damn the day he met her."

During the five months of this trial, much has been made of Knox’s sex life and her eccentricities, but what has been said about Sollecito has been just as bizarre. The now 25-year-old has claimed that Knox was only his second sexual encounter. Sollecito’s university residence hall supervisor Francesco Tavernise testified that Rafe was introverted and shy, but that he had once caught him watching a sexually explicit movie focused on bestiality. Sollecito also posted a picture of himself wrapped in surgical bandages brandishing a meat cleaver on his social-networking site, and the prosecution has pointed to his penchant for violent Japanese Magna comics that center on the occult. His only run-in with the law has been for possession of hashish on the beach near his hometown Bari.

Sollecito’s chief lawyer, Giulia Bongiorno, is the most sought-after defense attorney in the country, a Johnny Cochran-style legal star who, at 28, made her name as part of a powerful defense team that got then-Prime Minister Giulio Andreotti cleared of several Mafia-related charges. The fact that his father can afford her services is not lost on anyone following this case. Several of Dr. Sollecito’s patients in Bari have been accused of Mafia ties, and one journalist described him as “urologist to the dons.“ During the trial, local papers and courtroom staff have taken to referring to the various family members who sit in the back the courtroom and scowl at prosecution witnesses as the “the Sollecito clan.“

But even with his powerful family and expert counsel, there are problems within Sollecito’s defense team. Vincenzo Pascali, the chief forensic consultant who was set to give expert testimony about the possible contamination of the bra clasp, walked off the case last month, reportedly leaving a €50,000 bill. Back in September, Pascali, who declined to comment for this story, hinted that the clasp also contained Knox’s DNA. The bra clasp, which was collected some 40 days after the murder, is the most contestable piece of evidence in the entire case against Sollecito.

Bongiorno says her defense will focus on discrediting the evidence of the bra clasp, and on Sollecito’s alibi for the night of the murder. The two defendants are planning a joint defense, but Bongiorno admits her own client’s acquittal is her priority. Still, she often sticks up for Knox, vigorously cross-examining the prosecution's forensic witnesses and emphasizing lack of motive to argue for their innocence. Knox and Sollecito had only dated for six days before Kercher was killed. Last January, Bongiorno described the defendants as “two lovebirds in the first week of their romance,” not some “bored couple looking for excitement“ with group sex.

Early on in the investigation, however, Sollecito’s stepmother was wiretapped telling him to “erase the girl from your mind,” and court observers say the defense teams could split at the first sign of trouble. Legal analysts in Italy predict that Bongiorno will not risk her reputation to save Knox if things start to go bad. But even if she decides to abandon the joint defense strategy and put Sollecito on the stand, where he will be confronted by his sworn statements contradicting Knox’s alibi, Sollecito’s meek demeanor would make him a risky witness. It seems unlikely that he could project the same sort of confidence as Knox did last week.

In a two-page journal entry Knox wrote on November 7, 2007, the day after her arrest, she described a conversation she had had with Rafe about his drug use. “He told me that he drove his friends to a concert and that they were using cocaine, marijuana, he was drinking rum,” and how that experience had caused him to change. Knox also wrote how she counseled him. “I told him that life is full of choices, and those choices aren’t necessarily between good and bad. They are between what is best and what is not.” Sollecito's decision not to take the stand may be the most important choice in his life.

Barbie Nadeau has reported from Italy for Newsweek magazine since 1997. She also writes for CNN Traveller, Budget Travel magazine and Frommer's.