I am running a number of "do shell script" commands in an Xcode application and am able to run every command in the background (non-blocking) by using &.

This is an example of recon which can successfully be run in the background:
ex) do shell script "jamf recon > /dev/null 2>&1 &" with administrator privileges

For some reason however, the following policy command will NOT run in the background:
ex)do shell script "jamf policy -trigger someTrigger > /dev/null 2>&1 &" with administrator privileges

The weird thing is that both of the above commands work on Mountain Lion but the jamf policy command doesn't work on Mavericks...