Challenging a ruling that the prohibition was irrational, counsel for Mr Poots and his ministerial successors argued that devolved powers gave them the right to take a different position on the prohibition.
Attempts are being made to overturn a finding that the Democratic Unionist MLA did not have power to keep the lifetime ban on donations from gay men.
A High Court judge held that his decision was irrational and “infected” with apparent bias.
Mr Poots was also held to have breached the ministerial code by failing to take the issue before the Stormont Executive, and seemingly been influenced by his Christian beliefs in maintaining the lifetime ban.
It was replaced by new rules which allow blood from men whose last sexual contact with another man was more than a year ago.
But Mr Poots maintained the ban in Northern Ireland on the basis of ensuring public safety.
The findings against him were made in a legal action taken by a gay man granted anonymity in the case and referred to as JR65.
Challenges to the verdict have been continued by Mr Poots’ DUP ministerial successors and the British health secretary Jeremy Hunt.
The hearing at the Court of Appeal in Belfast had been put on hold pending the outcome of a European Court of Justice case.
In April it ruled that a lifetime ban may be justified in member states, but only if there are no effective detection techniques.
The court heard that following the judgment from Europe an assessment on whether the ban is proportionate will now have to be carried out.
Mr Poots was held to have acted irrationally by maintaining the ban on gay donations while importing blood from other countries who do accept MSM (males who have sex with other males) donors.
But barrister Margaret Gray, representing the Stormont department of health, argued that Northern Ireland is largely self sufficient in its own blood supplies.
There is little need to widen the pool of donations from outside, she contended.
“On the basis of that evidence it was reasonable for the minister to make the decision,” she said.
Ms Gray also emphasised one of the consequences of powers being devolved within theUnited Kingdom.
“There’s no requirement that all parts of the UK decide a particular issue in the same way – that’s the essence of devolved decision making.
“It’s apparent in this context of blood donations that (EU) member states enjoy a discretion; that discretion is also felt between parts of a member state.”
During the hearing it was stressed that any increased risk of infected blood, no matter how small, was an issue of public safety.
JR65’s legal team claimed it was illogical to maintain the permanent ban on gay men while deferral criteria for promiscuous heterosexuals is lax.
But Ms Gray said: “If there’s sufficient basis to determine there’s a high risk attaching to MSM, the fact that other categories who are also deemed to be high risk but not treated in the same way should not render the rest of the decision irrational.”
Meanwhile, Tony McGleenan QC, for Mr Hunt, argued that it was for locally elected representatives to deal with the issue of gay blood donations in Northern Ireland.
The appeal continues.