One of the attorneys for the family of slain Missouri teenager Michael Brown says Brown's parents wonder if Officer Darren Wilson has a conscience or is a cold-blooded killer. Wilson, the Ferguson, Missouri, police officer who shot Brown to death in August following a scuffle, said in an ABC interview last week he has a "clean conscience."

But attorney Benjamin Crump told CBS "Face the Nation" Sunday that Brown's parents, Lesley McSpadden and Michael Brown Sr., think Wilson lacks any remorse for the shooting.

“His mother and father don’t think Officer Wilson had any consideration for their child and they wonder if he ever had a conscience,” he said. “That’s troubling to them." Crump also said he thinks the grand jury process is "broken."

Wilson resigned from the Ferguson Police Department Saturday.

Another attorney for the family, Daryl Parks, told "Fox News Sunday" Brown's family is considering suing Wilson and the city of Ferguson unless they can reach a settlement out of court. He said the family is considering taking its grievance to civil court because it would be difficult for the federal government to prove a criminal civil rights case against Wilson.

“You have to show that he [Wilson] intended to violate his [Brown's] civil rights,” Parks said. “That’s a pretty high bar. That’s going to going to be a difficult for them to [prove].”

Massachusetts Gov. Deval Patrick addressed the issue in an appearance on NBC's "Meet the Press," saying he would have liked to see Wilson indicted.

“Without knowing all the facts, of course I wanted to see an indictment,” said Patrick, a former civil rights attorney for the Justice Department. “Mostly because I think a trial, and the transparency of a trial, would be good for the community. And because so many of us have the supposition that police officers are not going to be held accountable and not going to have to answer for the shooting of unarmed, young black teenagers.”

Law enforcement officials said police need to learn from the violence that erupted in the wake of Brown's shooting and last week's grand jury decision against indicting Wilson. Former New York Police Commissioner Bernard Kerik said on CNN's "State of the Union"  he thought the police response to peaceful protests was out of proportion, and that when things turned ugly and rioting began, the response was not aggressive enough.

Ferguson unrest A man walks past a burning building during rioting after a grand jury returned no indictment in the shooting of Michael Brown in Ferguson, Missouri, early Tuesday, Nov. 25, 2014. Photo: Reuters/Jim Young

Dallas Police Chief Malik Aziz said police departments need to embrace community policing. He told "State of the Union" the Ferguson department's inability to build community relations and not letting the community know what was going on helped escalate the situation.