I think your'e wrong.
When a warrant is not necessary
It is not necessary for the police to be in possession of a warrant in order to enter and search premises in the following circumstances:
To arrest a person for whom a warrant of arrest has been issued during criminal proceedings;
To arrest a person for an indictable offence, meaning any offences that can be tried by a jury in the Crown Court; these tend to be the more serious offences;
To arrest a person for an offence under the Public Order Act 1936 section 1 which states that it is prohibited to wear a uniform in a public place or at a public meeting signifying an association with a political organisation, without permission to do so;
To arrest a person for an offence under the Public Order Act 1986 section 4 which prohibits anyone placing another in fear of violence;
To arrest a person for using or threatening violence for the purposes of entering premises (Criminal Law Act 1977 section 6);
To arrest a person who is a trespasser on the premises and who has failed to leave those premises after being asked to do so (Criminal Law Act 1977 section 7;
To arrest a trespasser who has with him any weapon (Criminal Law Act 1977 section 8)
To arrest a person who interferes with an Officer of the Court when they are trying to enforce a judgment (Criminal Law Act 1977 section 10)
To arrest a person for driving or being in charge of a vehicle when under the influence of drink or drugs;
To arrest someone for failing to stop a vehicle when required;
To arrest a person for acts of animal cruelty under the Animal Welfare Act 2006;
To arrest a child or young person who has been remanded or committed to local authority accommodation;
Recapturing a person, including a young offender, who has escaped from custody;
Recapturing a person unlawfully running who is being pursued;
In an attempt to save a life or prevent injury to someone or serious damage to property.
Other than to save a life, or prevent injury or serious damage to property, the police can only exercise the above powers if they have reasonable grounds to believe that the person they are searching for is on the premises. In connection to searching for items, the police can enter premises in search of items only if the suspect has been arrested for an indictable offence and there are items relating to the offence that will be useful as evidence. In this case an officer of the rank of inspector or above must give their authorisation in writing.