"None of the professionals I have spoken with have said that the testing itself wouldn’t make any difference to the prosecution. They have all said I should have been tested. The quibble is ‘by who?"
If testing was common/normal practice then there would be an established plan and pathway for it to occur. Every night, every A&E will see multiple patients who are unwell and that they might have been/were spiked, so it would be a common pathway in use.
People who haven't worked in A&E might expect that this would occur there as they'll be collecting blood for other purposes, but it doesn't for several reasons - chain of evidence, cost, time, benefit among them when they're focus is treating symptoms and getting you well enough to get out the door.
Spiking has been going on for decades, it's not new. The fact as you've discovered no one you've spoken to clearly knows who does do the tests in your area shows that it's just not normal practice. I would suspect most cases aren't even reported to the police at all, the victim just left to get on with it.
To look at it another way, say someone has definitely been spiked, there's no doubt. But fortunately they were taken to A&E before anything else happened to them, they were treated and discharged. The police are now investigating - they need to obtain CCTV footage from all the venues that person attended to identify who spiked the drink, multiple cameras from each venue, trying to track the persons drinks through the night. Think about all the times those drinks will be out of shot or just not covered by a camera. Think about how terrible the quality normally is, especially inside a dark pub/club. We've all seen the pictures on the news of person wanted in connection of serious crime - que blurry shot you can barely make out the colour of the persons clothes let alone their facial features, How many hours would this take of police time to go through all of this though on the off chance they do get some definitive evidence, in the investigation of a crime where ultimately no one was seriously harmed....
Yes it's a serious crime, yes ideally they will be investigated and certainly no one reporting the crime will be told it won't be. But typically all that is going to happen with be to request video from the one venue, ?if they have a shot that covers the area at the time, quick play through and likely nothing uncovered and in x months time you get a notice of case closed/no further investigations.
Out of interest a quick google shows a news article from 'national world' reporting only 37 convictions for drink spiking offences from 2017 to 202o in the UK, that includes all those which involved sexual assault.
The i reports between between 1 January 2018 and 3 November 2021.that out of 15 responding police forces to a FOI request only 44 people were ever charged with offences, 15 people received cautions, no prosecutions noted.
In some cases, the victims also reported being sexually assaulted or raped.
I think lots of police dramas on TV give people an overinflated idea of the level of investigation that goes on behind the scenes. It would certainly fall under the police services remit to gather this evidence though but they'd need investment to do so and it's still only part of the puzzle. I mean if lots of suspects were being found not guilty due to a lack of forensics that's one thing, but I bet it's the identifying the suspect in the first place that's not happening.