Harriet Harman has avoided a police investigation over her late reporting of donations for her Labour deputy leadership campaign last year.

Ms Harman eventually won the contest to replace John Prescott as the Labour number two but found herself involved in controversy last autumn.

The proxy donor scandal eventually forced Peter Hain from the Cabinet in February after it emerged he had failed to report £103,000 in donations.

Metropolitan police officers are investigating Mr Hain’s failure but the Electoral Commission (EC), which only has the power to fine political parties, today announced it would not be doing the same for Ms Harman.

Instead the leader of the House of Commons received a slap on the wrists in the form of a letter “making clear that failure to report on time is a serious matter”.

In total Ms Harman failed to report two donations totalling £6,001 and two loans totalling £58,000.

In addition an “impermissible donation” was returned within the acceptable 30-day period but was reported to the EC late.

Ms Harman insisted the £5,000 donation she received from Janet Kidd, one of the intermediaries used by property tycoon David Abrahams in the proxy donor scandal, “in good faith”.

Although prime minister Gordon Brown and environment secretary Hilary Benn had turned down donations from Ms Kidd, knowing they were coming from a third party, Ms Harman survived the scandal where Mr Hain failed to do so.

In November last year she told shadow leader of the house Theresa May, who had been pressing her on the issue in the Commons: “The honourable lady can huff and puff but she will not blow this leader of the house down.”