Former US attorney says Trump's lies help Mueller -- here's how

A former U.S. federal prosecutor urged investigators and prosecutors in the cases against President Donald Trump not to be discouraged, because his lies can be helpful.

In a Tuesday interview with Rudy Giuliani by the Wall Street Journal, the former New York mayor dangled the idea that Trump still might testify for special counsel Robert Mueller and the grand jury. MSNBC host Nicolle Wallace said that every lawyer everywhere is shaking their head and claiming it’ll never happen because lawyers can’t protect Trump from lying.

But those lies can still be helpful, according to former federal prosecutor Chuck Rosenberg, who said that there is “no such thing as too much evidence.”

“Believe it or not, lies are helpful to a prosecutor, too,” he continued. “Not just because you can charge them separately. There's another reason why lies are helpful: people who lie, box themselves into a corner."

He explained that someone like Trump will ultimately commit himself to a story, even if he knows the truth is something different.

"Even if you don't believe it, you know what the story is, subsequently, at trial, they're stuck, right?" he noted. "And disproving a lie, proving that they lied to put it in plain English, is sometimes just as valuable to a prosecutor as obtaining the truth.”

When it came to Giuliani’s impact on the legal strategy, Rosenberg isn’t worried he’ll ever serve as any barrier to the actual investigation.

“In the end, if Bob Mueller feels he must talk to the president, and I imagine that any prosecutor would want to, there's another avenue, of course,” Rosenberg explained. “He can issue a grand jury subpoena. That will likely be litigated and my guess is, the special counsel will win. And the president will be compelled to sit for an interview. It's a long path. It might be a tortured path, but it makes more sense to me than this back and forth with Mr. Giuliani.”

He also noted that most of what Giuliani says is nonsense and he’s intentionally trying to sow deceit.

Watch the conversation below: