I’ve seen it a hundred times on cop shows and in the movies. Our hero finds a stash of white powder, dips his finger in and tastes it. “100% pure unadulterated heroin!” (That one is a direct quote from the David Janssen TV movie Warning Shot).
Am I right to be highly suspicious of this? I’ve known TV to lie to me before. 
Thanks for that. I’m assuming then that with cocaine it’s barely possible because of the numbing effect (although lignocaine would do that too and that’s useless for getting a buzz) but with heroin and other drugs quite impossible?
You will totally get a characterstic numb from cocaine, although I don’t know if you could differentiate it from lidocaine or benzocaine. Also cocaine tends to have a solventy smell to it.
For those who haven’t had the pleasurable experience of snorting a drug before, when you do it eventually goes down the back of your throat and a tiny bit mixes in with your mouth, so you get some taste there to get to know it.
I don’t think heroin has a particularly distinctive taste though.
Some of these new synthetic cathinones are seriously harsh, they actually burn. Whether you can differentiate between them I don’t know as I’m a bit old for all that now.
I didn’t read the article psychonaut posted, but cocaine has a very distinct taste.
If heroin is like other opiates, it’s probably bitter. If you had a bag of unidentified powder, and knew for certain that it was either heroin or (say) flour, then you could probably identify it by taste.
The general problem of identifying an unknown powder is very stupid to solve by taste. You have no idea what the powder could be—it might be something completely innocuous like flour, or it might be a deadly poison. Even if you’re certain that the substance is some sort of recreational drug, it’s still pretty stupid to taste it. Some drugs are sufficiently potent that putting even a tiny amount on your tongue will give you a massive overdose. For example, LSD is also a white powder, but its recreational doses are measured in micrograms—putting a macroscopic quantity on your tongue, or even on your skin, is a recipe for disaster (albeit likely a non-life-threatening one).
Tasting has never been part of law enforcement training so it would be difficult to testify as to why you know what it tastes like. And since you don’t know what is in that mysterious white powder you have found, its not a good idea to put it in your mouth. There are field testing kits or you can arrest them using the white powder as probable cause pending lab results. Even with the field kit results it will go to the lab as well.
I always liked Terry Pratchett’s parody of this trope.
I’m sure it is this. For TV and movies it’s probably a device to keep the plot moving. Let the audience immediately know that it is cocaine/heroin instead of adding 20 minutes to the story by showing cops smoking cigarettes and drinking coffee while waiting for the lab results to come back.
Except in rush jobs for life-and-death matters, I think it normally takes a lot longer than 20 minutes for forensic lab reports to arrive. The cops are probably looking at a wait on the order of days, weeks, or even months. Twenty minutes probably isn’t even enough time for the cops themselves to write up and submit the lab request and evidence.
It’s Iocane Powder - I’d bet my life on it.
But not, one hopes, against a Sicilian.
Especially when death is on the line… a ha, a hahaha <thump>
In short, heroin tastes like vinegar (acetic acid). Very distinctive taste and smell as well. I can go in more detail later if anyone would like.
Our evidence guy takes drugs to the lab maybe once or twice a month. More if the vice guys have been particularly busy. It takes several weeks before the results come back. We use the State Police lab. There are just a couple of regional labs that together cover the entire state. Because of this, the lab report is usually the last thing done. And usually not on the day of the arrest.
Pure heroin should be odourless. Any vinegar smell comes from impurities introduced through the acteylation reaction in its manufacture.
So let’s say you have a warrant and enter a house where there are pallets full of bags filled with white, powdery stuff.
Do you lecture everyone to wait a few weeks to a couple of months and if these lab results come back positive, then they are in for it?
Do you arrest them immediately? On what charge? How can you hold them that long without charging them?
Bags full of white powdery stuff= probable cause.
Lab results = beyond a reasonable doubt.
Probable cause is needed for an arrest.
I’m sure loach will respond beter, but I think there are field kits that would be sufficient for the arrest while the lab results would then be used in the court proceedings.
Also figure onto it that in order to get a search warrant there already needs to be probable cause. Most likely controlled buys that have already been tested, at least with a field kit. So drugs have been bought from the house. You find what appears to be drugs. Probably take a small bit to field test. Plenty of probable cause for an arrest.