And the number of submitted police reports that clearly contradict reality.
Now imagine how many smarter people than her just ran all the tests at normal speed, but faked the result. It'd be damn near impossible for them to get caught. I'd wager for every one caught, there are 10 that don't.
What would you do if you don't have money for a lawyer, and the police say that your unassailable DNA evidence was found on a now-dead acquaintance of yours, and your options are confess to the murder and get 10 years with opportunity for parole, or fight and get life?
Even if you knew that the police can lie, know you are innocent but can't prove it, and you believe that the DNA test is real or the police are willing to fake it, you might confess b/c that's the best option.
Canada: Yes
Australia: Yes
UK: looks like cant lie about evidence?
If the police are allowed to lie about evidence then this undermines the suspects chances for a fair trial (false confession). If the defense can show at a trial that the police lied during the interrogation, this would impact the chance for a conviction. At least this is how it works in the EU. In the US, I have the impression the judges don't take this into account.