The United Kingdom General Election 2015 – Party Spending Investigation was a probe involving the UK Electoral Commission, numerous police forces, and the Crown Prosecution Service into spending by political parties and candidates, primarily during the 2015 general election campaign. This co-ordinated investigation has been described as 'an unprecedented and extraordinary situation'.David Allen Green, 'The law and politics of the Conservative election expense allegations' (8 June 2016).

At national party level, the Electoral Commission fined the three largest parties for breaches of spending regulations, levying the highest fines since its foundation:Laura Hughes, 'Conservatives fined £70,000 and MP reported to the police following an investigation into election campaign expenses', The Daily Telegraph (16 March 2017). £20,000 for Labour in October 2016,Jessica Elgot, 'Labour fined £20,000 for undeclared election spending including for Ed Stone', The Guardian (25 October 2016). £20,000 for the Liberal Democrats in December 2016,Rowena Mason, 'Lib Dems fined £20,000 for undeclared election spending', The Guardian (25 October 2016). and £70,000 for the Conservative Party in March 2017.Ed Howker and Guy Basnett, 'The inside story of the Tory election scandal', The Guardian (23 March 2017). The higher fine for the Conservatives reflected both the extent of the wrongdoing and 'the unreasonable uncooperative conduct by the Party'.The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), quoting p. 38.

At constituency level, related alleged breaches of spending regulations led police to begin investigations into possible criminal conduct of between 20 and 30 Conservative Party MPs. Charges were not brought against most of those investigated, but on 9 January 2019, a Conservative Party activist, Marion Little, was found guilty on two counts relating to falsifying election expenses and given a nine-month suspended sentence and £5000 fine.

Background

Elections held in the UK are governed by the Political Parties, Elections and Referendums Act 2000 and spending on elections is governed under the Representation of the People Act 1983. Shortly before the election, the Government increased the amount of money that parties and candidates were allowed to spend on the election by 23%, against the advice of the Electoral Commission.

2014 and 2015 elections, Conservative Party

Electoral Commission investigation

From 18 February 2016 to 16 March 2017, the Electoral Commission investigated the Conservative party at national level for breaches of spending regulations in the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood; the 2014 European Parliament election; and the 2015 general election. (No irregularities were found regarding the European election.)The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), quoting p. 17.

The Commission was informed by an investigation by Channel 4 News, which revealed that the Conservative Party had spent many thousands of pounds centrally on 'battlebuses' to transport activists, and hotel accommodation for the activists, who went to campaign in marginal constituencies, finding that this expenditure might breach limits on election spending per constituency.The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), §6.

On 12 May 2016, the Commission took the unprecedented step of launching court action to force the Conservative Party to release documents.Laura Hughes, 'Conservatives receive High Court challenge to hand over election spending information', The Daily Telegraph (12 May 2016).

The Commission concluded that:The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), §8. The Party likely understated the value of the Party's spending on the by-election campaigns. The Party Treasurer, Simon Day, 'failed to ensure that the Party's accounting records were sufficient to adequately show and explain the Party's transactions with the candidates and/or their agents' in the by-election campaigns. The Party's 2015 General Election spending return was not a complete statement of its campaign spending payments and also failed to include all the required invoices and receipts.

The Commission fined the Party £70,000, noting its lack of co-operation during the investigation.The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), §§10–11.

The Commission found that Simon Day may not have fulfilled his obligations under the Political Parties, Elections and Referendums Act 2000 and referred him for investigation to the Metropolitan Police Service.

Police investigation

Claims of overspending in the 2014 elections came to light too late for police investigations due to a statute of limitations on such cases.Nick Hudson, ' "No police action" over Conservative by-election overspend claims' (23 Feb 2016), http://www.policeprofessional.com/news.aspx?id=25506. However, the Commission found cause for concern that campaigns in some constituencies breached the Representation of the People Act 1983, and could constitute criminal activity; its report referred the Conservative Party treasurer Simon Day for investigation to the Metropolitan Police Service, and the Commission passed evidence to relevant police forces for investigation and possible referral to the Crown Prosecution Service.The Electoral Commission, 'Investigation in respect of the Conservative and Unionist Party campaign spending returns for the 2014 European Parliamentary Election, and 2015 UK Parliamentary General Election, and in respect of the 2014 parliamentary by-elections in Clacton, Newark and Rochester and Strood' (16 March 2017), §§10–11, 50–55.

Widely publicised criminal investigations of individual MPs, agents, and other officials followed from the allegations (by mid-June 2016, 17 police forces were investigating 20–30 sitting Conservative MPs). As well as the "battlebus" campaign, letters sent out in the name of David Cameron have been implicated.

14 police forces referred cases to the Crown Prosecution Service for possible prosecution, concerning over 30 people (not all of whom were MPs).'Exclusive: CPS considering charges against over 30 people including Tory MPs over expenses' (18 April 2017). These forces were: Avon & Somerset, Cumbria, Derbyshire, Devon & Cornwall, Gloucestershire, Greater Manchester, Kent, Lincolnshire, Metropolitan, Northamptonshire, Nottinghamshire, Staffordshire, West Mercia, West Midlands, and West Yorkshire.'Police forces pass election spending files to CPS' (15 March 2017).'CPS statement on election expenses ' (10 May 2017).

Journalistic commentary noted that the law in this area is complex. Defendants may be found guilty of merely 'illegal practice' (where there is no alleged dishonesty) or the more serious 'corrupt practice' (involving dishonesty). Anyone convicted would have a right to appeal. In June 2016, the journalist David Allen Green opined that 'unless compelling evidence emerges of wrongful and dishonest intention – either on a personal level or as part of a conspiracy – then it is hard to see any charges or criminal prosecutions in respect of the allegations as they currently stand'. However, according to The Independent, 'in theory election results in individual seats could be declared invalid if laws are found to have been broken', and this could lead to new by-elections.'Tory MPs face being prosecuted for electoral fraud while they are fighting the upcoming general election campaign' (18 April 2017). No conviction would affect the legal standing of legislation previously passed with the involvement of convicted MPs.

On 10 May 2017, the Crown Prosecution Service announced that it would press no charges in almost all cases, commenting that 'to bring a charge, it must be proved that a suspect knew the return was inaccurate and acted dishonestly in signing the declaration. Although there is evidence to suggest the returns may have been inaccurate, there is insufficient evidence to prove to the criminal standard that any candidate or agent was dishonest'.

However, on 2 June 2017, charges were brought under the Representation of the People Act 1983 against Craig Mackinlay, who was elected Conservative MP for South Thanet in 2015, his agent Nathan Gray, and a party activist, Marion Little.'Conservative candidate Craig Mackinlay charged over election expenses', https://www.bbc.co.uk/news/uk-england-kent-40129826. Appearing at Westminster Magistrates' Court on 4 July 2017, the three pleaded not guilty and were released on unconditional bail pending an appearance at Southwark Crown Court on 1 August 2017. The investigation of Party Treasurer Simon Day remained ongoing.Rowena Mason, Anushka Asthana and Rajeev Syal, 'Tory candidates did nothing wrong on election expenses, May claims', The Guardian (10 May 2017).

Following some delays to the trial,Date set for Conservative MP's trial over election expenses The Guardian, August 15, 2017. Retrieved August 15, 2017. Gray was acquitted on 13 December 2018 and Mackinlay on 9 January 2018.'Tory aide cleared of falsifying election expenses claim ', The Guardian (13 December 2018). Little, however, was convicted of two counts relating to falsifying election expenses and given a nine-month suspended prison sentence and fined £5,000. The court concluded that Mackinlay and Gray had signed documents falsified by Little "in good faith, not knowing what she had done".'MP Craig Mackinlay cleared of election expenses fraud', BBC News (9 January 2018).

2015 General Election, Labour Party

In October 2016, the Labour Party was fined £20,000 by the Electoral Commission for under-reporting of election expenses at national level, which at the time was the largest fine the commission had imposed since being founded in 2001. The Commission noted the party's co-operation in its investigation. The same Channel 4 investigation that identified the Conservative Party's questionable spending failed to find substantial evidence of similar problems in the Labour campaign.Michael Crick, 'Did Labour’s Battlebus operation break the rules?' (13 June 2016).

At constituency level, police investigated allegations that several MPs breached local spending limits. In May 2016, Lancashire Constabulary announced that an investigation had been opened into Labour Party expenses following allegations that Cat Smith, MP for Lancaster and Fleetwood broke election spending laws. However, in November 2016 they cleared Smith of any wrongdoing and fully exonerated her. Other cases seem likewise to have been dropped.'Rotherham MPs face electoral expenses fraud probe', 22 August 2016.