So, I note that you’ve posted this question several time before but have never had a proper answer. I think one of the reasons for this is that its a hypothetical with a large number of potential outcomes.

To start with, it would largely depend on how and where you were discovered, who discovered you, what their attitude was, and the way you responded.

Its a rough generalisation, but if you were in the battle area, still had your rifle, and showed willing to go back ‘up the line’ there is a very good chance that nothing would happen at all.

In March of 1918 for example, some 25,000 ‘stragglers’ were rounded up by military police, fed and watered, and sent back up the line.

If you didn’t have your rifle, there may be a charge of ‘casting away arms’ which carried the same sanction as desertion or cowardice.

One example of this is the case of Lance Sergeant Stones, whose unit was the target of a German raid on the 26th/27th November 1916. Stones was the senior NCO on the watch when the raid occurred, during the course of which his officer was badly wounded and several men ran. Stones was stopped at a checkpoint about 750 meters from the firing line without his rifle.

Stones was charged with casting away arms. We don’t know the minds of the men who found him guilty but it seems likely that Stones excuse for not having his rifle – that he’d left it as a barricade while he went to get help – was viewed as being somewhat disingenuous.

Stones was shot at dawn.

Stones of course was an NCO and as such was expected to set an example. If NCO’s and Officers could not set a good example, then there was a likelihood that an example was going to be made of them.

For this we can see the case of Lt Dyett. On the 13th November 1916, Dyett, who had been Left out of Battle was ordered to join his battalion. In the confusion, Dyett became lost until he came upon another subaltern who was rallying a group of stragglers. Dyett refused to join this group, stating that he would instead go back to Brigade HQ for further orders.

Having been ordered up the line, and having refused the opportunity to do so, leaving a brother officer and a number of men in the lurch, Dyett was found guilty. Although the court recommend mercy, Hubert Gough, his Army Commander recommend the sentence be confirmed, the fact that he was an officer playing a role in his decision.

Dyett was shot at dawn.

Indeed, the chances of leniency not only decreased with increasing rank, but while conscripts were shown a degree of indulgence, professionals were held to a higher standard.

Such was the case of Pte Harry Farr, pre-war regular. On the 17th September 1916, Farr’s battalion was moving up the line. Farr asked permission to see a doctor stating that he did not feel well. The doctor found nothing wrong with him but he did not go up the line.

He was again ordered to do so and refused, telling Regimental Sergeant Major Haking, that he ‘could not stand it’. Then Hanking replied with the choice words

‘You are a fucking coward and you will go to the trenches. I give fuck all for my life and I give fuck all for yours and I'll get you fucking well shot’

Later a final attempt was made to escort Farr up the line. Farr physically resisted, broke free and ran.

Farr was shot at dawn.

Of the approximately 8.7 million men who served with the British army at some time in the war, there would only be 3,080 men sentenced to death, and of these only 346 were actually executed. Of these, 266 were executed for desertion, and only 18 for cowardice. In addition, most of those executed would have had a record of previous bad conduct, indeed several had already been sentenced to death once or even twice before. So in reality, for the majority, nothing would happen provided you had your weapon, were still in the battle zone, and showed willing to go back up the line.

For the small minority who were found guilty but had their sentence commuted, I don’t have extensive data, but it seems not uncommon for these men to be sentenced instead to a given number of years of penal servitude, suspended for the duration of the war.

The aim of the disciplinary process was to set examples. That if you behaved poorly, there had to be a realistic possibility that you may face the extreme penalty.

The army had no interest in shooting its own men, so perhaps the fact that so many faced no sanction or were effectively returned to unit with a blemished record is not that surprising when you consider those that did pay the ultimate price.