About 60% of the crimes reported to one of the UK's largest law enforcement agencies are not fully investigated due to resource constraints, the police chief said.
Ian Hopkins of Manchester Police said budget cuts forced officials to be more ruthless than ever before.
He said that about 600 crimes per day, such as vehicle thefts, would be "singled out" and not persecuted because "we do not have enough officers".
The Interior Ministry said it was "obliged" to ensure that the armed forces were adequately funded.
The number of frontline police across England and Wales has declined over the past decade as violent crimes increase.
The Greater Manchester Police (GMP) said it had lost about 2,000 officers during this time, to about 6,200.
& # 39; necessary evil & # 39;
"If your life is in danger and you have been seriously injured, we will emerge anyway," Hopkins told BBC Radio Manchester.
"If there is an immediate threat, we will be there and be in numbers.
"If your shed has been damaged, your bike has been stolen, your vehicle is damaged and there are no witnesses, there is no CCTV and there is no forensics option, we will check that quickly.
"Your likelihood of a police officer coming to terms with it is almost non-existent, and this is where the public really felt, and this piece worries me."
One of Mr. Hopkins senior officials, Supt Rick Jackson, said investigating crimes was "a necessary evil."
GMP is not the only force that reviews reported crimes based on the threat and likely evidence available.
However, it is believed that Mr. Hopkins publicly acknowledges the fact that the majority of the crimes reported to him are public, the first time that a police chief has considered this practice.
One man told the BBC that he had moved from Manchester to Rossendale in Lancashire after being "finally driven out of the house by a crime."
He said, "I broke into Cheetham Hill eight times in five years and stole vehicles.
"The police came and took notes, but did nothing.
"You can tell from the attitude, there was no forensic investigation, there was no one who made detailed notes and no follow-up."
He said he was "frustrated and annoyed," adding, "The police are a waste of time."
Bicycle thieves, pickpockets and pocket catchers not found
The police in Greater Manchester found no suspects in nine out of ten bicycle thefts, theft of people or vehicle crime, and more than eight out of ten burglaries.
Theft from the person includes pocket nibbles and pickpockets, but not raids and robberies.
Data for the year from March 2018 to February 2019 also show that one-quarter of violent and sexual offenses investigations were completed without a suspect being identified.
Other results, out of a total of more than four in ten, included everything from suspects sent to a court to investigations that were not prosecuted because it was not in the public interest.
The data did not contain antisocial behavior.
Crime in Greater Manchester
Investigations completed without identified suspects
In 2018, West Midlands Police Chief of Police said budget cuts had declined and the number of police officers had sometimes caused his troops to do "a disservice".
"We believe that the public desires that we use our time productively and focus our resources on the greatest damage and where we can achieve a positive outcome," said a spokesperson for the National Police Chief.
Police chiefs expressed concern about the impact of declining officer numbers on "proactive policing that avoids crime, solves problems and helps people feel safe," he said.
& # 39; Strong reality & # 39;
The decline in the number of police forces is mainly due to changes in central government funding, which have fallen by nearly a third in real terms since 2010.
Mr Hopkins said it accounts for about 80% of its budget.
"We were promised a review of the funding formula and that did not happen, but it has to happen," he said.
How many policemen are there?
Front officers in England and Wales
Increases in council taxes, as announced in February, which will pay an additional 320 GMP police, "will never give Greater Manchester the resources it needs," he added.
The new additions will increase the strength of the force to around 6,570, compared to 8,219 in 2010.
"The reality is clear that due to years of cuts by the central government, the police simply can not investigate every crime and make difficult decisions about where to best focus their time and resources," said Bev Hughes, deputy mayor of Greater Manchester is responsible for policing in the city region.
"She – and I wish this was not necessary, but unfortunately it is."
Lucy Powell, a member of Manchester Central, said: "It's clear that government cuts in police funding have a real impact on the front line, making it extremely difficult for officers to do their jobs effectively and for certain types of crime to react.
"This should be a wake-up call for ministers who should take action to increase resources to fight crime and disorder."
A spokeswoman for the Interior Ministry said police funding would rise by the largest amount since 2010 this fiscal year.
"We recognize the impact of crime on the victims and want criminals to be brought to justice.
"We are committed to ensuring that the police have the resources they need to do their vital work," she said.
You can learn more about this story on BBC Radio Manchester from April 23 to 30, as well as BBC Sounds.
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