The LEO pistol is a semi-automatic pistol that is polymer-framed and striker-fired. It is used by both the Croatian military and law enforcement. So you can consider using a police pistol to break the law as a form of bizarre poetic justice. At the very least, if the cops find any shells laying on the ground after a heist they will first be on the lookout for a renegade Croatian cop, so you can rest a little easier.
The LEO is a pistol whose low base damage is offset by its large magazine capacity and ammunition reserve. There are mods which can bring its damage up to respectable levels, but it has a limited modification pool compared to some other pistols. This pistol also has an unusually low hip-fire spread modifier on par with the Signature .40, which makes shots fired from the hip highly accurate.
Due to this gun's low hip-fire spread modifier, it is not necessary to aim down the sights when firing. Shots actually become less accurate when a player is moving and aiming down the sights compared to moving and firing from the hip.
Acing One Handed Talent helps with increasing the LEO's damage, allowing it to surpass 80 damage while having high accuracy and stability.
The LEO was based on the Springfield Armory XDM, the United States-marketed version of the HS Produkt HS2000 as can be seen from its many visual characteristics.
The in-game pistol bears the trademarked XDM grip pad pattern not found on Croatian-made HS2000s. It also features an interchangeable slide backstrap, again an addition by Springfield Armory.
The two slides of the LEO are those of Springfield Armory XDM pistols, as evidenced by their slide serration patterns. In reality these items are manufactured by Springfield Armory in the United States, and thus do not bear any marking related to "HS Firearms Croatia" as seen on the in-game models.
The LEO has markings on the slide stating it is a .40 S&W, while on the barrel it says it is a .45 ACP. Also, the magazine capacity is that of the 9mm model.
The LEO erroneously has an ambidextrous slide release and takedown lever. These parts are only designed for right-handed shooters on the real gun.
The description on the DLC's announcement site claims the pistol's casings are unique enough to instantly be recognizable to the police as those of the LEO. This is wildly incorrect on several levels, since most (if not all) of the XDM's marketed variants are chambered in very common pistol calibers, a large number of which are standard-issue for police firearms as well, making identification nigh-impossible and pointless.
The LEO contains several references to Lion Game Lion, the creator of the DLC in which this gun was released:
The embossed image of a lion head can be seen on the LEO's grip, near the edge of the magazine well. The same image can be seen on the slide, near the brass ejection slot.
Leo is also one of the zodiac signs; it represents a lion.
The weapon—both its ingame model and real-life counterpart—has ties to Croatia, where Lion Game Lion is based.
The term LEO is also an acronym for "Law Enforcement Officer". This is an allusion to Dragan's past as an Interpol Agent.