If you receive a error like the following:
[2/10/2016 6:51:54 PM.968] LSPD First Response:
[2/10/2016 6:51:54 PM.969] LSPD First Response: ==============================
[2/10/2016 6:51:54 PM.969] LSPD First Response: UNHANDLED EXCEPTION DURING GAME THREAD TICK
[2/10/2016 6:51:54 PM.969] LSPD First Response: ------------------------------
[2/10/2016 6:51:54 PM.970] LSPD First Response: Origin: Game fiber "<UNNAMED THREAD>".
[2/10/2016 6:51:54 PM.970] LSPD First Response: ------------------------------
[2/10/2016 6:51:54 PM.971] LSPD First Response: Exception type: Rage.Exceptions.InvalidHandleableException
[2/10/2016 6:51:54 PM.971] LSPD First Response: Exception message: Operation is not valid because the specified  Rage.Ped is invalid.
[2/10/2016 6:51:54 PM.972] LSPD First Response: ------------------------------
[2/10/2016 6:51:54 PM.972] LSPD First Response: Inner exceptions:
[2/10/2016 6:51:54 PM.972] LSPD First Response: ------------------------------
[2/10/2016 6:51:54 PM.973] LSPD First Response: Stack trace:
[2/10/2016 6:51:54 PM.973] LSPD First Response: at Rage.Entity.get_Model()
[2/10/2016 6:51:54 PM.974] at ?????????????????????????????????????????.?????????????????????????????????????????(Ped ) in E:\GTA V\LSPD First Response\LSPD First Response\Engine\Scripting\Functions.cs:line 1241
[2/10/2016 6:51:54 PM.974] at LSPD_First_Response.Engine.Scripting.Entities.Persona.?????????????????????????????????????????() in E:\GTA V\LSPD First Response\LSPD First Response\Engine\Scripting\Entities\Persona.cs:line 193
[2/10/2016 6:51:54 PM.974] at LSPD_First_Response.Engine.Scripting.Entities.Persona..ctor(Ped ped) in E:\GTA V\LSPD First Response\LSPD First Response\Engine\Scripting\Entities\Persona.cs:line 70
[2/10/2016 6:51:54 PM.974] at ?????????????????????????????????????????..ctor(Ped ped) in E:\GTA V\LSPD First Response\LSPD First Response\Engine\Scripting\Entities\CPed.cs:line 90
[2/10/2016 6:51:54 PM.975] at NK7>L$j\&2e\&6)>yunUnF\&_I{'.?????????????????????????????????????????(Ped ) in E:\GTA V\LSPD First Response\LSPD First Response\Engine\Scripting\Entities\CPedCache.cs:line 31
[2/10/2016 6:51:54 PM.975] at ?????????????????????????????????????????.?????????????????????????????????????????(????????????????????????????????????????? ) in E:\GTA V\LSPD First Response\LSPD First Response\Mod\SuspectTransportManager.cs:line 195
[2/10/2016 6:51:54 PM.975] at ?????????????????????????????????????????.?????????????????????????????????????????() in E:\GTA V\LSPD First Response\LSPD First Response\Mod\SuspectTransportManager.cs:line 89
[2/10/2016 6:51:54 PM.975] at Rage.GameFiber.Main()
[2/10/2016 6:51:54 PM.975] LSPD First Response: ==============================
[2/10/2016 6:51:54 PM.975] LSPD First Response:

 

This is a LSPDFR issue relating to the AI Suspect Transport, for now, you must ensure that no AI officer fully arrests somebody, always arrest yourself, or kill the suspect.

Same here