ANOTHER British athlete last week tested positive for performance-enhancing steroids, just 24 hours after the new £10m Olympic-accredited anti-doping laboratory was unveiled 30 minutes from the heart of the 2012 Olympic Park.

The two events are unrelated. The facility at Harlow had nothing to do with identifying the two steroids used by Bernice Wilson, an unheralded Jeannie-come-lately to top-level UK sprinting.

The Birchfield athlete improved by four metres in just 13 months at the age of 26 over 60 metres indoors, but tested positive less than three months after having broken into the GB team for the European Indoor Championships in Paris.

Because the offence was considered calculating and constructive in seeking to blame other people, the maximum four-year suspension was confirmed when her appeal was thrown out.

The signature of the cheat was evident – the "spike" of dramatic improvement in just a year, after several modest seasons. Her best time of 7.25 was equal 12th on the UK all-time list, and a performance which only four British women had bettered in more than a decade.

UK Anti-Doping confirmed to Herald Sport that during the financial year 2010-11 they conducted 7500 "test missions" which resulted in 24 "cases". These included those who had no valid reason for missing a test. That puts into perspective the scale of the Olympic operation announced last week for London. The Essex laboratory lies behind razor wire in the research headquarters of 2012 sponsor GSK, among the world's biggest pharmaceutical companies.

The biggest ever Olympic doping crackdown will screen half the competitors, some more than once. This will involve analysis of 6250 samples by 150 scientists. Around 1000 of these will be blood tests and will include every medallist.

In Sydney 2000, 2359 tests caught 11 cheats; Athens 2004 had 22 positives from 3667 samples (four athletes missed tests and two horses also tested positive), and in Beijing, four years ago, there were 4770 tests and 20 positives.

Professor David Cowan, director of London's King's College drug control centre, who heads the Harlow lab, is coy about details. He does not claim all cheats will be caught but feels recent advances will make it harder for cheats. All very laudable, yet I had a frisson of unease hearing him say competitors who challenge his science, "won't be successful. We are going to be fast, sensitive, and efficient, and we are going to be right".

The anti-doping movement has a record of smugness and, dare we say it, claims of infallibility. Professor Cowan should know better than most, as he has exposed them. Diane Modahl, former Scottish, British, and Commonwealth champion, proved an accredited Olympic laboratory wrong after she was banned for two years. It cost her her home, bankrupted her, and drove her to contemplate suicide. It was Cowan's testimony – that unrefrigerated sample storage could cause degradation – which led to Modahl's name being cleared. The scandal discredits and undermines the integrity of a well-intentioned process. Small wonder many athletes have little confidence in anti-doping.

Remember the 167 tests passed by Marion Jones, exposed as a serial cheat? And Germany's Olympic lab which showed that supplements are routinely contaminated, causing competitors to be banned, and careers to be destroyed? Many believe, as do I, that only the naive, careless, or stupid get caught. And it probably requires two of these factors. LaShawn Merritt, Olympic and World 400m champion, failed a test due to use of a cream, ExtenZe, sold for penile enhancement. It contained banned male hormone.

Merritt successfully argued at the Court of Arbitration for Sport (CAS) that he should be allowed to compete in London. This suggests the British Olympic Association will no longer be able to exclude convicted cheats from GB selection after they meet CAS in March.

The truth is that the greatest anti-doping victories are not thanks to the millions spent by the World Anti-Doping Agency, the Olympic movement, UK Anti-Doping and its counterparts worldwide. They are thanks to whistleblowers and law enforcement.

Jones was busted because she lied to the FBI. Ditto several other American sportsmen and women. And only after a jealous coach sent a sample of a product, disguising its anabolic properties, that the authorities cracked its construction using reverse engineering. This, and not WADA or the testing programme, brought down a catalogue of infamous names. One, double world champion Kelli White, testified she had passed 17 tests in and out of competition. Others exposed included world 100m record-holder Tim Montgomery, world indoor 1500m record-breaker Regina Jacobs, and Britain's European 100m champion Dwain Chambers.

It is worth encouraging whistleblowers, as cricket is now attempting to do to counter illegal betting. More tests are not the answer. GSK says there is no conflict of interest in sponsoring the Olympic test programme (a total contribution of £20m). This despite actually manufacturing drugs on the banned list.

Professor Cowan and his team, they insist, are completely independent. GSK gives research data on new drugs to the World Anti-Doping Agency, but WADA's fight would be more effective if all pharmaceutical companies would use bio markers.

This, especially if in conjunction with every global sports body copying the initiative of the International Association of Athletics Federations – biometric passports after taking blood from competitors – would make drug-free sport much nearer.