Addressing the Conservatives leader in the House of Commons tonight, Ms Swinson said Mr Johnson needed to say sorry following the Supreme Court judgement.
The court ruled on Tuesday that Mr Johnson's decision to suspend Parliament for five weeks was unlawful.
Judges said it was wrong to stop MPs carrying out duties in the run-up to the Brexit deadline on 31 October.
Ms Swinson said: "He needs to understand that actions have consequences. Even my five-year-old knows that if you do something wrong you have to say sorry."
SNP Westminster leader Ian Blackford referred to Mr Johnson's statement stating: "It wasn't the Supreme Court verdict, it was the judgement of the Supreme Court."
He said: "The Prime Minister was utterly humiliated by the Supreme Court. By a count of 11 to zero and you might have thought in that diatribe that we had that we might have had some humility."
Mr Blackford said: "Mr Speaker, sorry is indeed the hardest word for Prime Minister.
"It was said by a former prime minister where law ends, tyranny begins, and while it pains me to say it, the fact the Prime Minister is still standing here today, he in fact does believe he is above the law. Well he is not."
Responding to Ian Blackford, the Prime Minister said: "On his substantive point, we do respect the Supreme Court.
"The reason that I want a Queen's Speech, and wanted a Queen's Speech, is quite frankly of course because we had to do what we can as a United Kingdom to remedy the waste and the incompetence of high-taxing, fish-abandoning government of the SNP in Scotland."