The former Conservative council leader was suspended for the rest of the current Parliament in May by the Lords Privileges and Conduct Committee.
He was also ordered to repay £3,300 which he had wrongly claimed.
Following a complaint, the Lords Commissioner for Standards, ex-Hampshire chief constable Paul Kernaghan, carried out an inquiry focusing on 11 days in July last year when he spent less than 40 minutes in the parliamentary estate.
In his report, Mr Kernaghan found that in making the incorrect claims, Lord Hanningfield ‘’failed to act on his personal honour’’.
It has now emerged that the peer was questioned earlier this year as part of a police investigation.
The Metropolitan Police confirmed that “a review of allegations of unlawful claiming of allowances at the House of Lords” began after Mr Kernaghan’s report.
A spokesman said: “We can confirm a 73-year-old man attended by appointment an east London police station and was interviewed under caution in relation to an allegation of fraud.”
Lord Hanningfield’s case followed an investigation by the Daily Mirror, which alleged that he was claiming the daily allowance for peers while only spending short periods in Parliament.
In its report last year, the newspaper said it monitored his movements on 19 days in July 2013 and on 11 of them he travelled to Westminster from his home in Essex but spent less than 40 minutes in the Lords before returning. The shortest attendance during the month was 21 minutes and the longest more than five hours.
Lord Hanningfield said he regarded the allowance as a ‘’de facto salary’’ which earned him around £30,000 a year and was unaware that what he was doing was wrong. He made clear he intends to return to the House of Lords after his suspension.
He was jailed in 2011 for a separate abuse of his expenses.
Lord Hanningfield previously claimed that he could name 50 other peers who claimed allowances in the same way that he is alleged to have done.
But Scotland Yard said its investigation was “focused on Lord Hanningfield alone”.