The Electoral Commission is the independent body which oversees elections and regulates political finance in the UK. In accordance with the Political Parties, Elections and Referendums Act 2000, the Commission has a range of supervisory and investigatory powers which enable them to monitor compliance with electoral finance laws proactively and enforce suspected offences.
The Electoral Commission has civil sanctioning powers that apply to referendums and elections. More serious criminal matters can be and are referred to the police, and then considered by a court of law. The courts already have the power to levy unlimited fines.
It is important to remember that political parties are voluntary organisations and not large corporate organisations. Disproportionate regulation could discourage volunteering and undermine local democracy. Political parties and referendum participants of all colours have been fined for breaches of technical reporting requirements.
The Electoral Commission is operationally independent of government and is governed by the Commissioners. The Electoral Commission is accountable to Parliament through the Speaker's Committee on the Electoral Commission.
It is commonplace for the Government to set a broad policy framework, as approved by Parliament, by which independent regulators should work. This is already the case for Ofcom and Ofgem, for example. The Speaker’s Committee on the Electoral Commission and the Levelling Up, Housing and Communities Select Committee were consulted on a draft of the statement and the final statement needs to be approved by Parliament.