As the Conservatives go to court to prevent police investigating its South Thanet election expenses, Channel 4 News reveals fresh evidence of undeclared expenses there, and the scale of the operation.

Detailed new evidence from inside a Conservative campaign office in the key South Thanet constituency reveals the huge resources provided to this campaign.

Other documents and social media postings further reveal how staff from Conservative party headquarters were parachuted in to the constituency to help their candidate beat Farage, with many related costs not declared locally.

Channel 4 News understands that there are 18 police forces up and down the country that have been given or are seeking an extension to the time limit relating to election expenses.

The Conservative party is currently only attempting to block in South Thanet an extension to the legal time limit that the local police force has to investigate election returns.

Today, new evidence obtained by Channel 4 News reveals that an important battlebus visit on election day to South Thanet, up to a dozen promotional videos made for the local candidate, and a conference room used by a minister to campaign on local issues for the candidate appear to have never been declared.

The Conservative Party told Channel 4 News: “The Party always took the view that our national Battlebus, a highly-publicised campaign activity, was part of the National Return, and declared it as such. All spending has been correctly recorded in accordance with the law.”

Beat Farage

In the South Thanet contest, UKIP Nigel Farage was defeated by the now Conservative MP Craig Mackinley – by 2,800 votes. He was assisted by tens of thousands of pounds of spending that appears to have been used to help local campaigning – enough to take him beyond the £15,000 cap.

The new revelations come as the Conservative Party take the unprecedented step of trying to oppose a court extension to the police investigation into whether it correctly declared the money they spent in South Thanet. That hearing itself was in a closed court session not open to the public or press.

The Conservative Party bought in James Laddie QC, one of the country’s top lawyers, to attend the closed session at Folkestone Magistrates Court on Tuesday May 24.

Battlebus – final stop

Channel 4 News understands that on 7 May – election day itself – was the biggest campaigning day for the Mackinlay campaign. Staff and activists on the bus appear to have taken part in local campaigning to get out the vote for Craig Mackinlay. He tweeted: “Thanks to @MrMark Clarke and his @roadtrip2015 #battlebus2015 — 60 people on the way to lead charge in #SouthThanet.”

We can reveal that none of the £400 costs incurred by this Battlebus visit appear to have been declared.

Team 2015

Channel 4 News has also obtained evidence of repeated visits by bus loads of Team 2015 activists who appear to have campaigned for Craig Mackinlay MP. These include visits on 4 April, 9 April, April 11 and 12, and 26 April.

We have obtained video footage of the Team 2015 visit on 9 April which shows the then-party’s chairman Grant Shapps encouraging the activists to campaign for the local candidate Craig Mackinlay, who thanks the activists for supporting him.

None of the costs incurred on these Team 2015 visits appear to be on Mr Mackinlay’s candidate spending return, despite clear guidance from the Electoral Commission that the costs of campaigning for the candidate must be declared by them in order to promote fairness.

Links to Conservative party headquarters

In the Broadstairs campaign office – the campaign schedule was photographed by Emily Ashton, from Buzzfeed.

It stated that on the 9 April, the Transport Minister John Hayes MP visited Manston Airport which was at the time considered a major local issue in South Thanet. It was not a matter considered to be of national significance.

Channel 4 News has obtained evidence that a conference room was booked at the airport Holiday Inn hotel for a Conservative Party event on April 9. The booking was made in the name of CCHQ staffer Marion Little OBE.

None of the costs associated with this event appear to have been declared in the South Thanet election spending return. Nor does it appear to have been declared nationally.

This appears to fit into a pattern of apparently undeclared spending involving senior figures at CCHQ that has been identified by Channel 4 News in previous investigations.

The Electoral Commission is already investigating three by-elections in 2014, which took place in a “regulated period” when all spending should have been declared.

In those by-elections and in South Thanet, Channel 4 News obtained hotel receipts in Newark, Clacton, Rochester totalling some 770 nights of accommodation which were booked under Marion Little’s name and home address.

We have also identified some £4,000 of bookings made by Ms Little at the Premier Inn in Margate.

The law says any money spent promoting the local candidate must be declared by the candidate and their agent on their local spending return. Failure to declare is a criminal offence.

The hearing on whether Kent Police will be given a time extension – already granted to 18 police forces up and down the country – is due to take place on Wednesday next week.