Once there was time to examine the financial impact of the union the Bootle Watch Committee hesitated to move forward with the plan. In November, they requested a postponement of the proposed April date but it was rejected by the Home Secretary who urged negotiations to continue between the two police authorities. After much deliberation Liverpool agreed to an abatement of the sum Bootle would have to pay for the first two years.

With the obstacles removed, the Liverpool & Bootle Constabulary came into being on 1st April 1967 with the 172 members of the Bootle County Borough Police joining together with the vastly larger Liverpool City Police. On 29th March, Mr Harold Legg, the Chief Constable of Bootle County Borough Police since 1953, accepted an appointment as an Assistant Chief Constable to be based in Liverpool in the new Force. Mr Legg joined the Southampton Police in 1929 where he served until 1947, reaching the rank of Inspector. He was then appointed Deputy Chief Constable of the Barnsley Borough Police with the rank of Superintendent, serving six years in that post. A few weeks after the combined Force was formed he was awarded the Queen's Police Medal. Mr James Haughton, the Chief Constable of the Liverpool City Police, was appointed Chief Constable of the new combined Force, and was the only person to hold the position.

New insignia was not immediately forthcoming for the new Constabulary, with Liverpool City Police badges being issued until 1972. Many holdouts of the previous Force continued to wear their Bootle County Borough Police insignia during the transition. Within the short period of its existence, and even shorter period during which new badges were issued, only two metal cap badges, one for Constables and Sergeants, and one for the upper ranks through Chief Inspector, and a helmet plate for Constables and Sergeants were eventually issued. No collar badges were produced, with those of the two constituent Forces continuing to being worn.

The first month for the Liverpool and Bootle Constabulary was a difficult one for many reasons but especially due to a rash of break-ins and with the Force begin 546 Officers under strength. Male candidates between the ages of 19 and 30 were sought to fill the deficit with free housing or a tax-free rent allowance provided in addition to starting salaries of:

1. £765 at age 19
2. £800 at age 20
3. £835 at age 21
4. £870 at age 22 or over

1. 5 Superintendents class II to become class I
2. 3 Chief Inspectors promoted to Superintendent class I
3. 5 Inspectors to Chief Inspector
4. 8 Sergeants to Inspector
5. 10 Constables to Sergeant

The Liverpool and Bootle Constabulary maintained a Mounted Section under Inspector Philip Barry, which held an annual Horse Show, a Dog Section of nearly forty dogs and an Underwater Search and Recovery Section among others. The latter were all volunteers that would swap their uniforms at a moment's notice to take on a watery assignment. Six Policemen staffed the Unit in 1968, which formed before the amalgamation within the Liverpool City Police, in 1962, all drawn from the swimming section of the Police Athletic Society and having passed a series of thirty-six tests before being accepted to the Unit. They trained once a month during duty hours in canals, flooded quarries and the sea and weekly on their own time at the Police Training School on Mather Avenue. The Section grew to eight members by June of 1969 when it was proposed to disband the Unit with the Cheshire and Lancashire Constabulary Diving Sections to assume the role for all of the North West.

The cornerstone of the Dog Section was Axel who was the first dog in Britain to be trained to sniff out hidden drugs. Axel was only months old when he joined the Liverpool City Police, the pet of Sergeant Tom Benson who donated him to the Dog Section and became his trainer and handler. Axel died whilst still serving with the new Force in January of 1972. At age 10 1/2, he was twelve months past retirement age but he was so exceptional he remained on duty. In his final year alone, he had seventeen successful drug prosecutions to his credit.

Chief Inspector Florence Dean became the first woman in the Liverpool and Bootle Constabulary to retire on pension. She became a Women's Auxiliary Constable in 1940, joined the Liverpool City Police in 1948, was promoted Sergeant in 1949, Inspector in 1952 and Chief Inspector five years later. She was responsible for the supervision of Policewomen in the Force when she retired in April of 1969 after twenty-five years' service. By 1972, there were over 150 Women Police under the charge of Superintendent Edna Evans. They covered all forms of Police activity other than Special Branch, including radar patrols, motor patrol and CID where there was a team of 15 plainclothes Policewomen, comprised of thirteen Constables and two Sergeants under Inspector Barbara Gale.

The Force continued to be under strength in 1970, with an authorised strength in the 'A' Division of 369 but an actual count of only 291 Officers. The Force overall was short of its authorised strength by 600 Officers, critical enough that an undermanning allowance was paid of £1.25 per week, due to the deficiency in numbers of 21.5%. The allowance, which required Home Office approval, was meant to be an aid to recruitment. The Liverpool and Bootle Force was not the only one in need of such a boost at the time as it was also being paid to the Metropolitan Police and the Glasgow City Police. Another measure taken to address the shortfall was to increase the number of Traffic Wardens appointed for the Force in order to free additional Officers for Police duties. Attempts to increase recruitment also included the Force holding a Police recruiting month from 26th October to 21st November, inviting suitable applicants to a mobile "Evening Patrol" taking anyone interested in joining the Force on a night patrol in a radio equipped vehicle to "Look into the world of a Policeman". Seventy of 183 applicants went on a night patrol. The operation was such a success it was repeated in January of 1971.

The new 'B' Division Headquarters in Marsh Lane, Bootle, came into operation in December of 1972 and opened officially in the following April. About 400 members of the Force worked out of the new buildings which replaced the former Victorian premises in Oriel Road that was originally opened as the Bootle County Borough Headquarters in 1891.

The strength of the Liverpool and Bootle Constabulary finally improved in 1972. In the first half of the year, 85 men and 20 more women were recruited. Also, about 150 of the 277-strong Docks Division were soon to be re-allocated as the South Docks were due to be closed in September as part of economising measures by the Mersey Docks and Harbour Company. The Dock Division consisted of 225 Constables, forty-one Sergeants, nine Inspectors, one Superintendent and one Chief Superintendent. All were members of the Liverpool and Bootle Constabulary but were paid for by the Dock Company.

The question of policing of the Docks was discussed in earnest in October of 1973, with the Dock Company desiring to setup their own private 250-man docks police force with a Chief Constable and police style uniform. To move forward an Act of Parliament was required with the benefit of returning 150 Policemen to ordinary duties within the Liverpool and Bootle Constabulary. However, The Mersey Docks and Harbour Police Order would not offer any relief to the Liverpool and Bootle Constabulary as it did not come into operation until after the Force ceased to Exist. It was not until the 19th of June 1975 that the Port of Liverpool Police were established. This new Force had responsibility for policing the Dock Estate in Liverpool and Birkenhead, taking that weight off of the successor to the Liverpool and Bootle Constabulary.

That successor was the new Merseyside Police Force that came into being on 1st April 1974, formed by the amalgamation of the Liverpool and Bootle Constabulary and sections of the Lancashire and Cheshire Constabularies under the Local Government Act, 1972.