LONDON—Britain’s government doubled down on its defence against accusations of cronyism on Sunday, arguing that former leader David Cameron’ failure to get support for finance firm Greensill Capital showed its lobbying rules were “pretty good”. Questions over whether former ministers and civil servants are granted easy access to the Conservative government have been raised by the behaviour of Cameron and other officials. Cameron has denied breaking any code of conduct or government rules and the government has repeatedly said the outcome of his discussions on failed firm Greensill’s proposals for access to a COVID-19 loan scheme were not taken up. But Prime Minister Boris Johnson has launched an independent review to look at the allegations and several parliamentary committees are also launching inquiries into the role of lobbyists and ministers’ interests in private companies. George Eustice, the environment minister, said he believed Cameron had done nothing wrong, but agreed with …