The investigation into possible collusion between President Donald Trump's campaign and Russia is a "serious issue," but there may be more worrying matters to focus on, former Homeland Security chief Michael Chertoff told CNBC on Tuesday.
"I'm worried about 2018. I'm worried about 2020. Do the Russians try to interfere with our election or our kind of civic discourse going forward?" he said in an interview with "Power Lunch."
Both the Senate and a special counsel are investigating what may have occurred between members of the Trump campaign and Russian officials during the 2016 election.
On Monday, Trump's son-in-law, Jared Kushner, denied he colluded with Russia and said his actions while serving on the campaign were "proper." His comments came after he met with Senate Intelligence Committee staff on the matter.
Meanwhile, special counsel Robert Mueller is reportedly also looking into a broad range of transactions involving Trump's businesses as part of its probe, Bloomberg reported last week.
His investigation is also looking into a meeting between Donald Trump Jr. and a Russian lawyer. According to Reuters, Mueller has asked the White House to preserve any records of that meeting.
Chertoff, also a former U.S. assistant attorney general, called that request routine.
"I was a prosecutor for many years. Every prosecutor says that. That's like saying the sun rises in the East."
Trump and his team have vehemently denied any wrongdoing.
— CNBC's Jacob Pramuk and Everett Rosenfeld contributed to this report.