One of the troubling questions at the center of the impeachment inquiry, at least for Republicans, has been the work that Hunter Biden did for Burisma, one of Ukraine's largest gas companies, while his father was serving as Vice President. But the intensity of interest in Washington is only making it more difficult to resolve the mystery.

To this day, Burisma's connection to Hunter Biden has made it much harder for Ukrainian authorities to investigate the company for corruption, current and former officials in Ukraine tell TIME. In that sense, Burisma is still getting its money's worth for the reported $50,000 per month it paid the younger Biden to sit on its board from 2014 until earlier this year.

Ukraine's government insists that it has no evidence of wrongdoing by Hunter Biden or his father. But Burisma, they say, is a different story. Since taking office in May, the government has sought to explore past claims of corruption against Burisma and its owners. Yet, as an unintended consequence of the impeachment inquiry, Ukraine has felt the need to treat the company with kid gloves.

"It's too sensitive a topic," says an official in Kyiv, who would only discuss the company's case on condition of anonymity. "I think that we need to investigate Burisma. Not for Trump. And not against Biden. We need to do that because this is just a case of corruption," says the official, who is familiar with the thinking of Ukrainian President Volodymyr Zelensky. But the impeachment inquiry has "changed the context" around alleged corruption at Burisma, adds the official. "And this is bad."

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The case of Burisma cuts to the heart of the Republican defense of Trump. The U.S President and his allies have insisted that the Bidens acted corruptly to shield the company from prosecution in Ukraine. The former Vice President, his son and their supporters have strenuously denied these allegations, and there is no evidence that Joe Biden's decisions were ever influenced by his son's involvement with Burisma. But the treatment of that company in Ukraine suggests that the role of Hunter Biden continues to affect the handling the company's case, prompting the new government of President Zelensky to weigh its approach to fighting graft with particular care, especially when it comes to the country's notoriously corrupt gas sector.

"We don't know how major players in the United States would turn any statement" on the issue of corruption, says Bohdan Yaremenko, a senior lawmaker in the ruling party of President Zelensky. "If we would try to make an emphasis on this issue right now, we would sound like we are trying to contradict President Trump and Republicans."

During a press conference in Kyiv on Wednesday, Prosecutor General Ruslan Riaboshapka told reporters that there are more than a dozen criminal cases in Ukraine that involve the company or his owner. They will all be reviewed in due course, he added.

Ignoring them is not much of an option for Ukraine. "We cannot not investigate it just because it will benefit Trump or hurt Biden," says the official, who believes, "It's a case of corruption." But given how radioactive the Burisma case has become in Washington, the government is not eager to pursue it in the midst of the U.S. presidential race. "We can do it after the elections," the official tells TIME.