Mr Hookem, who is also calling on members to sign the petition with the same request, said that Mr Patterson's sentence did not have to be custodial and pointed out that the former special forces operative was out of the country for the SAS weapons amnesty.
"Mr Patterson is a well known and well respected member of the private security industry now he has left the Armed Forces," wrote Mr Hookem.
"He has worked in some of the toughest environments in the world, including Helmand Province, where his work in bringing water and electricity to local communities helped the ISAF 'hearts and minds' strategy."
Mr Hookem said that the suspended sentence given to Dale Robinson last month demonstrated that Mr Patterson could have his sentence reduced to a suspended sentence, "showing that the British justice system can differentiate between a hardened gangland criminal who uses weapons on a regular basis from a man who has served his country and keeps a memento of those who made the ultimate sacrifice."
Read the whole letter here.