Like good police everywhere, China's finest invest equal measures of inspiration and perspiration to get their man.

But the Chinese sleuths portrayed in 21 secret police reports enjoyed extraordinary powers to ensure a high success rate. They searched homes at will, relied on extensive intelligence gathering, trapped suspects into incriminating themselves and extracted confessions sometimes after "intense struggle."

Their techniques often were crude but unusually methodical, using trigonometry to figure out the cause of a public bus bombing or running thousands of laboratory tests to trace a small plastic slipper to a big-footed rapist.

No crime was too small, no clue too insignificant for the dogged detectives who would come out in force -- even desk clerks and sick officers--to work through the wee hours on a wintery night to find a stolen Army pistol.

In their search for suspects, investigators often dipped into the deep pool of information routinely gathered about ordinary citizens in China.

The closest equivalent in the West would be the system of police informers, but China's intelligence apparatus goes much farther. Cities are organized down to "street security" personnel who collect the smallest details of everyday life. In factories and rural villages, official and unofficial informers keep tabs on their charges.

Detectives who view the world like a jungle stalked their prey with the confidence that "the clever fox will have difficulty escaping the eye of the hunter."

When suspects outfoxed the hunter, police set traps to snare them.

Investigators who had good but unsubstantiated reason to suspect an optometry shop employe of stealing $3,400 arranged to have him sent on an out-of-town trip so police could monitor his spending habits.

When the young man, who earned just $18 a month, was seen doling out cash "like flowing water," he was deemed as good as guilty.

Since courts basically are for sentencing, not trying law breakers, police act as prosecutors as well as investigators. They pile up evidence, confront their suspect in interrogations and only rest after he acknowledges the crime.

Of the 21 major cases where the culprit was captured, all resulted in confessions. The accused were variously described in the reports as "sweating profusely," "pale-faced" or "nervously twitching."

A few cases, however, were cracked only after hours of forceful questioning and accusations. Suspects who sought to remain silent eventually were compelled to talk; those who resisted ultimately gave in.

In northern China, a former convict arrested in an epidemic of murders and armed robberies refused to confess despite police evidence of his fingerprints at one of the robbery sites. Keeping quiet for nine days, he even had the temerity to accuse police of violating his civil liberties by holding him without formal charges.

Investigators decided to press charges and continued to compile evidence, according to the report.

Seven days later, the prisoner reportedly "laid down his arms" and admitted 27 cases of murder and armed robbery.