R v IRC, ex parte Preston [1985]

Preston
made agreement with Revenue to forgo interest relief which he claimed and also
pay some tax.
In
return Revenue would not raise further inquiries on certain tax affairs.
Four
years later, Revenue did make these inquiries.
Preston
sought JR.
House
of Lords held Preston had no remedy for breach of representation as such,
because Revenue could not bind themselves in one year not to perform their statutory
duty a few years hence.
But
JR was available because court could
direct Revenue to abstain from exercising its powers where unfairness to
applicant of doing so rendered such insistence an abuse of power.