Former vice president Joe Biden denounced the chants of “lock him up” that have followed President Donald Trump at various public events and peppered several Democratic rallies in recent weeks, saying that the party shouldn’t mimic Trump’s own crowds.

“I don’t think it’s a good idea that we model ourselves after Trump and say ‘lock him up,’” said Biden. “Look, we have to bring this country together. Let’s start talking civilly to people.”

The comments from Biden came during the Democratic presidential debate on Wednesday night and were another case of the former VP making a call for restored civility in a primary season that has witnessed more than a bit of blood thirst from the base. Chants of “lock him up” first made news when Trump attended a World Series game in Washington, D.C., and, subsequently, at a Bernie Sanders campaign rally.

Biden was asked, initially, if he would support a criminal investigation of Trump should he become president and the current White House occupant be out of office. He demurred, saying that such calls should be at the discretion of an independent Department of Justice.

“It is the attorney general of the United States, not the president’s private attorney,” he said, underscoring the prosecutorial independence of the post.