Animal rights groups have accused the government of ignoring expert reports when it granted planning permission for a primate research laboratory.
Planning permission for the scheme runs for five years
Lawyers for two lobby groups are challenging a decision made by Deputy Prime Minister John Prescott.
In the High Court on Monday, they said his ruling to give Cambridge University permission to build a testing facility had been a "foregone conclusion".
They want the decision quashed - even though the plans have now been dropped.
On Monday, Neil King QC, for Animal Aid and the National Anti-Vivisection Society (NAVS), said planning permission was granted "regardless of the outcome of a public inquiry and expert reports".
The university's £32m scheme had been thrown out by local planners because of police fears about public safety and rejected by an independent inspector at a public inquiry.
But permission was still given when Mr Prescott overruled the planning inspector and approved the facility "in the national interest".
The two groups believe the decision, made in November, was "perverse, unreasonable and unfair".
Even though Cambridge announced in January it would not be building the facility because of the general costs involved, the lobby groups are concerned the permission would be valid for five years.
This would, in theory, allow the university to change its mind and opt to proceed after all.
Mr King said Mr Prescott's conduct following the planning inquiry was "plainly unfair".
'Acting under dictation'
He argued the deputy prime minister failed to consider all the evidence which was put before the inspector, including evidence from the animal rights coalition.
"It must be plainly unfair on the claimants if the secretary of state has copies of the evidence submitted to the inquiry he can refer to, but he didn't have ours," he said.
Mr King added that there were genuine alternatives available to primate research but Mr Prescott did not engage those arguments.
"The reasons he gave for granting permission are that Lord Sainsbury (the science minister) said this is of national importance."
Mr King said this was a sign Mr Prescott failed to properly consider if there was a real need and "surrendered his independent judgment by acting under dictation".
Government lawyers will defend the decision.