A former U.S. attorney told MSNBC on Sunday that President Donald Trump's son, Donald Jr. is still lying when it comes to the meeting in June with Russian attorney Natalia Veselnitskaya, who reportedly told Trump Jr. that she had damaging intelligence on Democratic presidential candidate Hillary Clinton.

Ex-U.S. Attorney Joyce Vance said, "So, it looks like Trump Jr. is now engaging in what prosecutors call incremental truth telling -- when you have a problem that you're sitting on top of, you tell just as much as you think you have to tell to put yourself into the clear. And then you tell a little bit more, and a little bit more."

Trump Jr. has given conflicting stories about what Veselnitskaya said in their meeting. At first, he said the conversation was about adoption. Then, on Sunday he admitted that Veselnitskaya had offered to reveal compromising information to him about Clinton, but says that the claims didn't make sense and that he dismissed them.

Vance said that whatever Trump Jr.'s intentions were, he should have contacted law enforcement when approached by a foreign agent offering access to stolen information.

"If they were in fact hearing allegations that the Clinton campaign was in bed with the Russians, your intuitive response just as an American citizen is to reach out to law enforcement," she said. "Even if it's not true. You do that out of an abundance of caution. So if in fact they were not stunned by this, did not think it deserved comment to law enforcement, I would be surprised. I think it would be an indication that perhaps this isn't quite the truth yet and there are a few more steps in truth-telling before we get to the bottom of this story."

Watch the video, embedded below:

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Part Two: