Unfortunately I see both sides of this as a government retiree. The term is Taxpayer Dollar Cost Effectiveness which goes this way -->
Its not the crooks caught and who are found not guilty on a fight in the jury room over what reasonable cause is that get a District Attorney's Office its funding next year. Its the crooks that are convicted because they had did not have the possibility of any doubt in the jury's mind that get the budget funded.
If the DA cannot convict them, then why should the police arrest someone against whom the evidence is less than beyond all doubt. YES indeed, the standard for criminal evidence is "Beyond Reasonable Doubt" here in the U.S. and most British derivative law systems, but if the DA is not delivering, most of the political supporters for adequate funding for the police departments on up do other things with the T/P dollars. They want to see blood in the Arena, and the crime victims blood does not count.
I still like the idea of a justice system based on "beyond reasonable doubt" for evidence of a crime, but it took me two damn years of Law School to understand what that means. I am pretty darn sure the average politician does not understand the crap shoot behind it though.
PS Not to mention the folks that elect the politicians.