In a word, yes. But if established procedures to change laws hold, it would be extremely difficult, requiring Supreme Court action or a change in the Constitution.
Source: Can Libel Laws Be Changed Under Trump? – The New York Times
And amusing. What, say you? Can any story with this headline be amusing? Yeah, kind of. Notice, especially, my bolding of the last sentence:
The question is whether Mr. Trump would benefit from changing libel laws. Filing a lawsuit would open him up to discovery, which could lay bare details he might rather keep private. It should be noted, however, that Mr. Trump has a history of filing libel lawsuits, though he has never won in public court, according to a recent report. (Even if the libel laws do not change, Mr. Trump could continue to threaten news organizations with lawsuits.)
There is also the possibility that loosening libel laws could affect him in unexpected ways.
“Changing the laws to make it easier to sue would essentially be used to harm him,” said George Freeman, the executive director of the Media Law Resource Center and a former assistant general counsel of The New York Times. “He’s more likely to be a libel defendant than a libel plaintiff.”