When Joe Biden was asked during a recent news conference whether he had a conflict of interest leading Ukraine policy while his son was working for a Ukrainian oligarch, he said, "I'm not going to respond to that" and told reporters to focus on President Trump. If he's allowed to get away with that at Tuesday's Democratic presidential debate, it will be a travesty.

The debate moderators -- CNN's Anderson Cooper and Erin Burnett and New York Times national editor Marc Lacey -- have a responsibility to press Biden to address his conflicts. Worryingly, Burnett recently said "There is no evidence of Joe Biden doing anything wrong" and that "what we need to talk about right now is what did the president ... do or not do." That's exactly what Biden is hoping for Tuesday night.

Here are eight questions Biden should be required to answer during the course of the debate.

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1. Your son Hunter took a position with a Ukrainian natural gas company, Burisma, just before you visited Kiev and urged Ukraine to increase its natural gas production. He was paid as much as $50,000 a month despite having no experience in Ukraine or the natural gas industry. Why do you think Burisma hired your son and paid him such massive sums?

2. You say that you pressured Ukraine to fire its chief prosecutor because it was universally believed that he was not investigating corruption. Let's accept that. The Code of Federal Regulations states that when a federal official takes action that will affect "a relative with whom the employee has a close personal relationship" and "the circumstances would cause a reasonable person with knowledge of the relevant facts to question his impartiality in the matter, the employee should not participate in the matter." Even if the prosecutor deserved to be fired, you clearly had a conflict of interest because a reasonable person could question your impartiality. Why was it appropriate for you to be the one to deliver the ultimatum?

3. Secretary of State John F. Kerry's stepson, Chris Heinz, was your son's business partner and warned him and Devon Archer not to get involved with Burisma. Why couldn't Kerry, who had no conflict, take the lead on Ukraine?

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4. You recently said that you have "never spoken to my son about his overseas business dealings." But your son told the New Yorker that you did. Why did you say you never discussed it with him when you had? And why would you say to him "I hope you know what you are doing" if he was doing nothing wrong?

5. The same New Yorker story reports that in December 2015, "Amos Hochstein, the Obama administration's special envoy for energy policy, raised the matter [of Hunter's relationship with Burisma] with Biden." Hochstein may be called to testify under oath in the Senate about that conversation. What did he say to you?

6. In December 2013, your son flew with you to Beijing aboard Air Force Two. Less than two weeks later, his firm, Rosemont Seneca Partners, closed a deal to open a fund whose largest shareholder was the Bank of China. Would you have a problem if Donald Trump Jr. traveled to Beijing on Air Force One and then a few weeks later struck a major new commercial deal with the Chinese government? If so, why was it not a problem for your son Hunter to do this?

7. Your son announced this week that if you are elected, he will not work on behalf of any foreign-owned companies and will comply with all regulations "to address purported conflicts of interest, or the appearance of such conflicts." If his foreign work would be a conflict if you were president, why was it not a conflict when you were vice president?

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8. Many Americans are deeply concerned about Trump's attacks on the news media. But in recent weeks, your campaign has written to the major television networks to "demand" that they not invite the president's personal lawyer, Rudolph W. Giuliani, to appear on their programs, and has accused The New York Times of "active participation in [a] smear campaign" against you for publishing an opinion piece that criticized you. Why is this appropriate? And as president will you use the power of your office to coerce news organizations to silence those critical of your administration?

Biden is trying to intimidate the media into not asking tough questions about his conflicts of interest in Ukraine and China. Will CNN and The New York Times give in to his demands? We'll find out Tuesday night.

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