evidence: A Treasury minister is being investigated by Parliament's standards watchdog over a failure to register rental income on a London property. Tulip Siddiq, Economic Secretary to the Treasury and Labour MP for Hampstead and Highgate, north London, is under investigation for the late registration of interests, according to the Parliamentary Standards Commissioner's website. [...] Former Conservative MP Bob Stewart is being investigated for failing to declare an interest and an alleged lack of cooperation with the watchdog's inquiry.