McNamee said: "You have somebody who runs really strategic defense and aerospace projects for the federal government who's actively undermining the government that's paying him. And somewhere in that is a legal case that needs to be prosecuted," told Fox News.
McNamee was responding to a hate speech watchdog's report which found Elon Musk guilty of spreading "false or misleading claims about the US election" through his posts on the social media platform, which had garnered "nearly 1.2 billion views."
McNamee argued that there should be limitations on Musk's free speech rights because SpaceX has government contracts.
SpaceX has long been a major partner for the US government in launching military satellites. Documents reviewed by the Wall Street Journal earlier this year show the company entered into a massive $1.8 billion classified contract with the US in 2021.
"The critical element in thinking about Elon Musk is that, like any American, he has a right to his own opinion, and he has a right to express his opinion," McNamee began on MSNBC.
"However, that right is not unlimited. He is under some special limitations that would not apply to normal people because his company, specifically Starlink and SpaceX, are government contractors and, as such, he has obligations to the government that would, for any normal person, and should for him, require him to moderate his speech in the interest of national security."
Musk filed a lawsuit last year against the hate speech watchdog, The Center for Countering Digital Hate, arguing the claims in the report were "misleading."
They claimed the nonprofit's "scare campaign" cost the social media platform millions when advertisers fled.
The group's CEO Imran Ahmed defended the report in a previous media appearance. "The truth is that [Musk's] been casting around for a reason to blame us for his own failings as a CEO, because we all know that when he took over, he put up the bat signal to racists, to misogynists, to homophobes, to anti-Semites, saying Twitter is now a free speech platform. He welcomed them back on," Ahmed said on CNN last year.
But not everyone thinks that Musk should sew his mouth shout for the good of the world. Republican presidential candidate President Donald Trump announced last week he would appoint Musk to lead a government efficiency commission if elected in November.