Others, like The Bear Traps Report founder Larry McDonald, were more optimistic and suggested the findings could be a boon to certain sectors.
"It frees him up to focus on infrastructure and housing reform," McDonald said. "We will rally on this but everything that took us down last week will keep rearing it's ugly head again."
Here are the full comments from market investors, strategists and analysts:
Art Hogan, chief market strategist at National Securities
"No one fully contemplated an impeachment: It's just so hard to do. That's always been the fallback position. The thinking was there could be disruption, but that it could never unseat the president."
"It's been like an aching joint. We've never seen market reaction to this. It's always been that one market catalyst that has always been right around the corner."
"We may well have removed a nagging concern, but the current concerns like the China trade war and overseas grief that outweighs that. The disaster du jour on Friday was PMI and the global economy."
"We're going to pretty much roll into the first-quarter earnings season. And we all knew the economy was slowing, but have we priced that in? Does this earnings reporting season give us a corporate American that guides us down again or have we gotten everything in place?"
Larry McDonald, founder of The Bear Traps Report
"It frees him up to focus on infrastructure and housing reform."
"We will rally on this but everything that took us down last week will keep rearing it's ugly head again."
"The fact that these tariffs may not be going away is having a negative multiplier effect on the global economy. There's a massive GDP destruction going on."
Bruce McCain, chief investment strategist at Key Private Bank
"I think that most people have discounted the findings of the Mueller investigation in comparison to the Chinese trade war and tensions overseas trends."
"I don't think that it really has had the sort of play in depressing securities or giving them boost. When you resolve uncertainly people like it, but I don't really see any specific area to watch."
Stephen Weiss, founder of Short Hills Capital Partners
"I think the market was going to bounce back anyway and this gives it a little extra oomph. But overall the investigation rarely was a big concern for investors. If there is a big pop on this, you can likely fade it."
Jeff Kilburg, CEO of KKM Financial
"This cloud has now dissipated and this should allow markets to breathe a sigh of relief."
"This could be a real positive for the market if it allows Trump to focus on getting the Chinese trade deal concluded."
Peter Boockvar, chief investment officer at Bleakley Advisory Group
"While we might have a bounce, the markets I do not believe was focused one iota on the Mueller report. In fact, I've never ever myself even once mentioned him and the investigation as a factor impacting markets."
—With reporting by Fred Imbert and Yun Li