Thing is I'm not a schoolkid and I'm not angry....I wouldn't bother trying to convince a Jehovah's witness they were wrong about their faith and that's why I feel debate here is often pointless...it's the same mindset
In my opinion your assumption that you are always right and everyone who disagrees with you is wrong makes debate pointless.
You quote the opinions of those who agree with you, and ignore the opinions of those who don't. In the Gilroy case the opinions which count are those of the police, the COPFS and the trial judge. The first two decided to include the dog alerts in the evidence they used against Gilroy and the judge allowed the evidence to be included.
If you wish to castigate anyone, then Gilroy's defense team are the ones who failed him. Jack Davidson QC was an experienced criminal barrister whose sole argument seems to have been that the jury shouldn't convict Gilroy because the evidence was circumstantial. He was correct, but as the The Scottish Criminal Cases Review Commission allegedly reported, there was enough there to convict Gilroy without the evidence of the dog alerts.