Atropine is a recognized treatment for bradycardia, even that caused by heart block. ACLS teaches this nation-wide. It is part of prehospital protocols in many jurisdictions. It would not be difficult to defend in court at all.
This statement is closed-minded, dogmatic, intentionally inflammatory, and wrong. It is not malpractice, and I don't know who convinced you of that. As illustrated in previous posts, there are clinical indications for atropine in heart block.
Intentionally causing pain to elicit a physiological response is a draconian way of practicing medicine. If you want to increase sympathetic tone, you can administer a sympathomimetic agent, like dopamine or dobutamine or norepinephrine or epinephrine, which I see as far better than torturing the patient. Increasing sympathetic tone, by drugs or by causing pain, carries the same risks that you ascribe to atropine of increasing myocardial oxygen demand. And so will TCP. I've given quite a bit of atropine, and I do not see it as "dangerous" in the proper clinical setting, and is very well tolerated overall. TCP carries issues as well, if the patient is in such severe pain that they are trying to rip the pacer pads off their chest, then it's not "more efficient" than atropine.
Then why do any treatment at all? Just load them in the truck and take them to the hospital if that is the way you want to go. Your differential diagnosis must guide therapy. You have to think critically about what is causing the patient's condition and act accordingly.
'zilla