SUE Gray left Labour staff “in tears” after carrying out a heavy-handed leak inquiry into the £28billion U-turn.
Party officials have accused Sir Keir Starmer’s top aide of inspecting their phones and conducting interviews without a union rep present.
Some have reportedly filed a complaint and claim she violated due process with her investigation.
Ms Gray last week tried to identify the source of press stories that Labour was about to abandon its pledge to spend £28billion a year on green projects.
The reports plunged the party into turmoil as shadow ministers denied the claims only for them to turn out to be true.
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Labour officials were said to be left “in tears” by the nature of her inquiry, The Times reported.
Ms Gray famously carries out the Partygate probe during her time as a senior civil servant.
Labour insist no phones were confiscated but some people agreed to hand theirs over.
It is also understood a formal complaint has not been raised, but that informal concerns have been.
