Philadelphia prosecutors have found no evidence that suspect Edward Archer has any links to terrorism, though federal authorities continue to explore that issue.
Archer's lawyer said he may instead have mental health problems.
"The evidence is quite clear," said defense attorney Trevor Borum after Thursday's preliminary hearing. "I agree with you on that. However, whether or not he was acting under the influence of a mental illness, whether or not he could differentiate right from wrong at the time that happened, that needs to be explored."
Archer, 30, was held for trial on attempted murder and other charges. He used a stolen police weapon in the attack and emptied the chamber, authorities said.
Officer Jesse Hartnett testified about how his left arm was shattered by gunfire as he used it to cover his head in the vehicle the night of January 7th at 60th and Spruce Streets in West Philadelphia.
He said he later kicked the door open to pursue Archer, shooting him three times, before he went to the trunk of his cruiser to look for a tourniquet. Help soon arrived, and two other officers apprehended Archer a block away. They found the gun wrapped in the long white cloak he had been wearing.
Hartnett, 33, spent two weeks in the hospital after the attack. He has endured seven surgeries and has an eighth scheduled.
"The fact that he had his wits about him, to think, 'I need to go back to my patrol vehicle; I need to get a tourniquet,' I can't imagine anyone doing that," Assistant District Attorney Allison Borgatti said after the hearing.
Police Commissioner Richard Ross and other officers filled the courtroom to support Hartnett during his testimony.
"He recounted the circumstances of that horrible night in an exemplary fashion," Ross told Action News after the hearing, "and we'll see what happens."
Archer told detectives after his arrest that he believed police enforce laws that undermine the Quran's teachings, officials have said.
"I follow Allah. I pledge my allegiance to the Islamic State, and that's why I did what I did," Homicide Capt. James Clark has quoted him as saying.
Investigators believe Archer traveled to Saudi Arabia in 2011 and to Egypt in 2012, FBI special agent Eric Ruona said previously. The FBI this week declined to comment further on their ongoing investigation.
The weapon, a 9 mm Glock pistol, had been stolen from a Philadelphia police officer's home in 2013, police officials have said. It's not clear how it made its way to Archer, who was also charged with receiving stolen property.
He is due back in court March 31 for an arraignment.
The Associated Press contributed to this report.