Aidan O’Neill, setting out his case on behalf of SNP MP Joanna Cherry and 77 other parliamentarians, warned justices they risked a “Dredd Scott” moment if they rule in favour of the UK Government - a controversial reference to a US Supreme Court judgement that black people were not full citizens.
Drawing on literary and historical references from Burns to Kipling and Macbeth to the 1966 football world cup, Mr O’Neill argued that suspending parliament for five weeks amid a growing crisis over Brexit was an abuse of constitutional power.
"Stand up for truth, stand up for reason, stand up for diversity, stand up for Parliament, stand up for democracy by dismissing this Government appeal and upholding a constitution governed by laws, not the passing whims of men,” Mr O’Neill said in impassioned closing remarks.
"What we have with prorogation is the mother of parliaments closed down by the father of lies. Lies have consequences - but the truth will set us free.
"Rather than allow lies to triumph, this court should listen to the angels of its better nature and rule that this prorogation is an unlawful abuse of power of prorogation which has been entrusted to the Government.
"But this Government has shown itself unworthy of our trust as it uses the power of office to which is corrosive of the constitution and destructive of the system of parliamentary representative democracy on which our union polity is founded.
"Enough is enough. Dismiss this appeal and let them know that. This is what truth speaking to power sounds like."
Mr O'Neill also told judges that the government would normally not resort to "low, dishonest, dirty tricks - but I'm not sure we can assume that of this government".
In Scotland, the cross-party group of MPs and peers supported by legal campaigner Jolyon Maugham QC of the Good Law Project won a ruling from the Inner House of the Court of Session that prorogation was unlawful because it was "motivated by the improper purpose of stymieing Parliament".
But at the High Court in London, the Lord Chief Justice Lord Burnett and two other judges rejected a challenge from campaigner and businesswoman Gina Miller.
The Supreme Court is hearing appeals in both cases at the same time over three days.
Referring to the Government's failure to submit a witness statement or affidavit to the court, Earlier, Sir James Eadie QC, representing the Prime Minister, said Mr Johnson did not advise the Queen to suspend Parliament for five weeks for any "improper purpose".
Mr Eadie told the 11-strong panel that the suggestion the prorogation was intended to "stymie" Parliament ahead of Brexit is "untenable".
During a series of exchanges with the judges on the second day of a historic hearing in London, the barrister also said any attempt to call Mr Johnson to give evidence in court would have been "resisted like fury" had it been made.
Sir James told the court on Wednesday: "Parliament has been considering Brexit for months and years.
"It has had the opportunity to make whatever legislative provisions it has wished over that period and it has, in fact, made a plethora of legislative provisions - including and starting with the authorisation of the giving of the Article 50 notice."
He also said decisions to prorogue Parliament "are inherently and fundamentally political in nature" and not a matter for the courts.
However, during an exchange with Lord Reed he accepted there are limits to the Government's prerogative power and that it is part of the court's role to determine what those limits are.
Lord Wilson asked Sir James why no statement had been provided to explain why the prorogation decision was taken.
He said: "Isn't it odd that nobody has signed a witness statement to say 'this is true, these are the true reasons for what was done'?"
Sir James replied: "My lord, we have the witness statements we have.
"My submission is that, in light of the case law only, it remains open to the court to make judgments on the facts on the basis of the underlying documents that have been produced."