Sir Malcolm Rifkind has faced up to the inevitable and stood down as chair of parliament’s intelligence and security committee. To seasoned Westminster watchers, the circumstances appear wearily familiar: a hidden camera, a bogus foreign company, an MP (and former foreign secretary) boasting of services he can provide for money. Before this particular sting, which also ensnared former Labour cabinet minister Jack Straw, there have been many others, catching parliamentarians of every stripe appearing to trade influence for cash.

Both senior statesmen deny improper conduct and have referred themselves to the parliamentary standards commissioner to determine the extent of any wrongdoing. But even if Sir Malcolm is exonerated, he showed a dismaying lack of judgment that warranted resignation from his important role. An apparent willingness to offer diplomatic contacts to an unknown Chinese firm raise justifiable concerns. These will not have been quelled by Sir Malcolm’s claim to have acted as a former cabinet minister and not a current MP.

This is a tawdry end to a distinguished political career. Sir Malcolm’s experience and heft were valuable on the ISC, which is tasked with grilling politicians and intelligence officers on matters of national security. But the integrity and independence required for the role is also why perceived conflicts of interest cannot be ignored. He also appeared to forget his ￡81,936 taxpayer-funded salary, describing himself as “self-employed”. This will have done little for Tory party attempts to appeal to the ordinary voter, and helps to explain Sir Malcolm’s decision not to stand again in the upcoming election.