Fox News' Dana Perino was perplexed by all the lying people tied into the Trump campaign have plead guilty to lying and it took a while, but James Trusty, a former Justice Department prosecutor finally agreed that telling the truth has been difficult for Trump's associates.

After the news broke about Michael Cohen's new plea deal, Fox News' The Daily Briefing With Dana Perino brought on James Trusty, who is a frequent guest to discuss what had happened.

Many Fox News pundits were downplaying and attacking Cohen for implicating Trump and his former campaign associates for trying to do business with Russia while campaigning for the presidency in 2016.

Suddenly, pleading guilty to felonies over constant lies to Congress and federal investigators is not really a crime for Fox News anymore unless that person is a Democrat.

And it took him a hot minute, but Trusty finally agreed that the amount of lies being told by Trump's people was fueling the investigative engine - so to speak.

Perino asked, "You need to explain what a false conviction means."

Trusty explained that they are serious crimes but then tried to minimize them by saying, "it is fair to call it a process crime."

See, what's a little lying among peers?

He continued, "It's a situation where witnesses are not giving up the substance of what the investigation is actually focusing on, but instead tripping up on dishonesty. It's not a great moment for the Mueller investigation to keep racking up false statement charges or maybe even convictions because it's really getting further away from the core mission."

I'm sorry, it's not Mueller's fault if so many interviewees are committing felonies by lying to the federal investigators. Mueller has an obligation to prosecute them and then try and get to the truth.

Perino replied, "True, but what do you think -- I mean, there seems to be a lot of lying going on."

Trusty said, "Right. I mean, look, I think it's interesting to figure out when their discretion to charge this takes place, but the bottom line is, if you accept that these are provable instances, which certainly in Mr. Flynn's case he's pled, now Mr. Cohen has pled to a false statement charge. The others have as well."

"Exactly, then you get into a situation where you say, even if it's not conspiratorial, man, you got a lot of people having a real hard time telling the truth and that certainly stokes the investigative engine in a way as well.

We know Trump lies like no other president in office, but he's not under oath when he does it as far as we know.

But why would so many of Trump's people lie so willingly if there was nothing to cover up? As Judge Napolitano said, this is only the tip of the iceberg and Mueller has the iceberg.