This summer residents of the three counties will be asked whether they support changes which create one force that would stretch from Bournemouth to the Isles of Scilly.
Already an alliance between the two constabularies sees joint work across 19 functions and has resulted in more money for frontline policing.
But Devon and Cornwall’s Police and Crime Commissioner Alison Hernandez will tell a meeting of the police and crime panel in Plymouth that she will only support the merger if the public are behind it and there is a clear business case to make the change.
The precept levied on households to pay for policing is currently £18* lower in Devon and Cornwall than in Dorset, and a formal coming together would change this over time.
“There is a shared view from the chief constables that a merger of the two forces offers the best long-term solution for all parties,” Alison said.
“However, in considering the future it is important that we understand the community impact of any decisions in this area. I will not support a merger unless it is in the best interests of the people of Devon and Cornwall.”
Alison is urging members of the public to carefully consider the implications of a merger and take part in a major engagement exercise that will open this month and run across the summer.
Questionnaires will be available online and at dozens of events such as district shows as the Office of the Police and Crime Commissioner seeks to garner public opinion on the changes. OPCC staff will be available to answer questions and to help people understand and have their say on the proposals.
Today’s meeting at Council House will also hear about plans to increase police officer numbers and hold police community support officer numbers at 200 by 2020.
Alison will also outline proposals to build upon an initiative that has seen communities pay for extra PCSOs. The scheme enables organisations such as Business Improvement Districts and local authorities to fund officers.
“The decision to hold the total number of PCSOs across Devon and Cornwall at 200 by 2020, rather than the previously planned 150 by 2021, is welcome,” she added.
“I am also keen to support innovative new ways of funding PCSOs. They can play a vital role in the community policing mix.”
*£18 is the difference between band D properties in Dorset and in Devon and Cornwall.