"He keeps getting shot down. He wanted to do impeachment, he wanted to subpoena and get some kind of charge against Bill Barr for not answering the subpoena and he either gets shot down by Pelosi or somebody else. He really can't get what he wants," Asman said on "Outnumbered."
The session with Dean begins a series of hearings in which House Democrats are attempting to keep the spotlight on Special Counsel Robert Mueller's report.
President Trump blasted Dean as a "CNN sleazebag attorney" Sunday in a nod to Dean's appearances on the cable news channel.
Nadler announced Monday that the Justice Department agreed to release to his committee some of the underlying evidence from the Mueller report.
Asman said in politics, "you're judged on the basis of your success."
"So far Jerry Nadler hasn't had a lot of success," he claimed about the Judiciary Committee chairman, adding that Democrats want to "discredit" Barr before he releases findings on the origins of the FBI's Trump-Russia probe in 2016.
Democrat Jessica Tarlov, also appearing on "Outnumbered," pushed back, arguing it's too early to say whether Nadler's tenure on the committee has been successful.
She said Mueller could testify before the committee soon, according to Nadler, though Mueller said recently he would not expand on what is in his investigative report.
Tarlov argued that the public seeing Mueller on camera could sway public opinion on impeachment.
"We know how powerful it is to actually see people talking about this," she said, pointing out the significance of Mueller saying in front of the cameras that if his team had "confidence" Trump did not commit a crime, they would have written it in the report.