Why don’t you click on the link, read the article, and find out?

But I have heard of it in other places.

In some cases the weapons are turned into the playthings of the police department and pretty much ruined.
Any ammo is used up by the the cops for fun.

In one case a legal semi auto carbine was abused by the cops so much it failed and went full auto on them. The owner was then charged with possession of an illegal full auto weapon.
I am not sure if the charges stuck but the weapon was never returned,

Police departments represent and reflect the prosecutor. Make sure that if you have a chance to elect them that you elect trusted and reason able conservative ones. The same with judges.