An exception can be made to this rule in cases where the overwhelming public interest justifies publication or broadcasting and in as much as the elements covertly obtained cannot be obtained by any other means. It is also justified when recording or filming could put the life of the journalist in danger or totally distort the behaviour of key players, always under the condition of overwhelming public interest. In such exceptional cases, the journalist should always take care to protect the identity of people who happen to be present at the scene by chance. Even under these special conditions, journalists can refuse to participate in covert research for reasons of conscience.