The phrase 'has been expedient' is correct and can be used in written English.
It is used to describe something that has been useful or necessary in a particular situation. For example, "Buying the extra supplies for the project has been expedient in order to guarantee its successful completion."
But city officials said they had concluded that while settling small-scale federal lawsuits might have been expedient, it did nothing to discourage lawyers from bringing marginal lawsuits.
Splitting the commission may have been expedient: producing even a single set of doors is a lengthy process for an artist.
This may have been expedient during the cold war, to protect diplomats from being framed (as well as blackmailed and honey-trapped).
Driving the weak into the arms of the strong may have been expedient, but it swelled the oligopoly of financial conglomerates deemed too big to fail.Mr Kaufman draws a convincing link between this consolidation and greater market vulnerability.
For the Athenians, the treaty had been expedient, but it was never popular.
For each of them the disembodied American definition of the terrorist challenge has been both expedient and convenient.
But it has been politically expedient for Congress to renew the act, rather than add places where discrimination is a problem today.
For years, it has been politically expedient for major news outlets to cover up the truth and impose news blackouts on all serious issues, especially the Kurdish conflict.
Gone has been the expedient of quotas, which sought as a direct policy to integrate players of colour into the side, occasionally at the expense of white cricketers of superior ability.
This has been politically expedient, allowing the Conservatives during the coalition government to time-limit, condition and sanction a key benefit – and now cut it – while claiming the "vulnerable disabled" are being protected.
