DS12 pressures to shoplifted

[SleeplessinEastSussex]

I had a call yesterday from DSs school to say that he and 2 other boys had been shoplifted a couple of energy drinks. A member of the public heard someone talking about it in the street and called the school. Apparently some of the other kids in the year had told them to do it and they wanted to fit in with the popular crowd.
I then had a call 30 mins later to say that he had been told off for writing on another boys arm.
I am worried he's falling in with the wrong crowd.
I took him to apologise to the shopkeeper and pay for the energy drinks, he's lost all devices and grouded for the weekend but is there anything I can do long term to prevent him wanting to blend in with the popular kids and not being so easily led?

Hang on...how did "a member of the public" know your son's name and how was the stealing proved? Was he caught on camera?

Also, don't assume that it's peer pressure. I well remember being the ringleader at my school....people assumed I was following other kids but it was all me. I was bored...always needing something exciting to do and had no outlets.

Is he interested in any sports or perhaps drama? "Naughty" kids often excel at drama because it's thrilling.