Hi, ooh the debate has started!
The MATS 1 point is really, that just because a procedure exists in MATS 1 does not mean that it is appropriate for your unit to use it. By this I mean that the unit may chose to use a subset of MATS 1 procedures, just because it is there does not mean that you have to have it. There are some areas where you may chose to develop additional procedures, subject to CAA approval, which do not conform to MATS 1 and operate as a "trial" etc...
On the subject of endangering an aircraft, it would be most unlikely for an ATCO in England and Wales (now why can I see half of Prestwick resigning at this point and heading for Southampton?) to be prosecuted successfully without deliberate rule violation errors coming in. If for example, you deliberately vectored an aircraft into a hillside in IMC because it was flown by your wife's new boyfriend that she left you for, well maybe we get into the realms of possibility.
The point of law, now again, please do not fry me here, you may need this...., is that an air traffic controller is responsible for the following
(i) turning up to work approximately on time
(ii) to have had sufficient rest
(iii) to be in a fit physical state
(iv) to be in a fit mental state
(v) to want to do a good day's work (should be shift really)
(vi) to apply the procedures given by management to the tasks
(vii) to use the training and experience in applying those procedures.
Your job is not to make up new procedures on the spot. Your job is not to take shortcuts with the current procedures. Should you wish to change a procedure, put it to management and say why. They may (i)either ignore you, in which case carry on with old procedure (ii) tell you why the procedure change is inappropriate (iii) change the procedure having done the safety analysis.
Now, I do not wish to knock controllers in any way, but you would be defended against a manslaughter charge on the basis that you are an "operator" in the system, not that full responsibility rests on your shoulders alone. That is the point of SMS, you know where you sit. You do not carry insurance, your employer does. You will find that expert evidence and a good barrister (yes, I know one...) have managed to argue successfully for other system operators in multiple manslaughter charge cases, such as most train drivers.
I used the word "appear" as I am confident in what it says, but we have not had it tested in case law. I hope we do not either!
By interpretation of the phraseology, what I meant was that if you have a procedure and its associated phraseology, it will be defined somewhere what is meant by it. It should be what is meant in MATS 1, but remember, some units do different things. Remember the holding point and holding position argument? Many units are not very good at explaining procedures to controllers, just bang out another Temporary Operating Instruction and off we go....
The unit safety case should have all of the boundaries for the application of procedures listed within it. The MATS 2 may not. This is where MATS 2 formats tend to be hopeless. Many are about 40 years out of date in terms of good procedure format, but ATC are a conservative lot....
The MATS 2 should explain why the procedure is there, the hazards that it is designed to manage, the scope and boundaries of its application, the required equipment and say MET conditions, who can use it and when, what training is required and all of the operational limitations, contingency procedures etc, not just the procedure itself.
In fact, you should find that airport related procedures come from the Aerodrome Manual first, then into MATS 2, but that is a whole other subject (oh, I might excuse LBIA as they do airport and ATC in house, and the other units like that).
IF and only IF your MATS 2 contains all of the information you need to apply a procedure, then that is where you have to look. If it does not, then at least tell management that you are missing some of the important operational application limits in it. I can assure you that the instructions to the controller at the heart of the mid-air over Germany had a set of operating instructions that were not worth the paper they were written on.
What I would also say is that we are trying to get it right in the UK. You should see the rest of the world, with a few exceptions.