The main political parties are breaking the rules of branding with their current campaign materials, according to research carried out by brand and design consultancy Further.

Tactics cited in the research include publishing material that appears to be local free-sheet newspapers but are actually party propaganda pieces. There is evidence of parties adopting another’s branding – for example, the Liberal Democrats have adopted Labour’s red colour for their news sheets in Hackney and Islington. Employing a similar technique, the Conservative Party produced a campaign newsletter in Watford entitled ‘NHS Matters’ using NHS branding. The newsletter was actually a Conservative note defending its position on hospital cuts.

Adrian Day, managing partner at Further said: "Imagine leading commercial brands passing themselves off as the competition – say, Shell adopting BP's green and yellow colours, or Vodafone adopting the Orange colour? This copying can only cause confusion amongst the electorate. At a time when the behaviour of politicians is under scrutiny as never before, it’s frankly staggering that this sort of practice i's happening."

There are potential legal implications for such tactics.

“The main parties all have registrations for their names/logos and so using another party's registered trade mark unfairly could amount to trade mark infringement." said Tom Lingard, senior associate at Stevens & Bolton, LLP.

In practice however, it's unlikely that any of the main parties would head to the courts.

"No party would want to be seen scoring points by resorting to law so, unlike in a commercial environment, there is little incentive for them to do so” added Lingard.