Standard style when citing different authors from the same group
This is most likely a field-culture thing, but I find it very odd that you would treat the three papers as anything but independent pieces of work. If you want to indicate that the three papers are part of a series, you could always say something like 


  a series of papers [1,2,3] presented blah blah


On the one hand, you want to give the "group leader" prominence, and on the other hand you clearly recognize the potential unfairness. I can imagine some of my students being rightly upset if their dissertation work was referred to as "work from the lab of Prof. Venkat". 

I realize that many lab-driven disciplines are top-down in this way, but since there's a perfectly reasonable way to cite the work, I'd avoid highlighting the "lab leader" any more than merely by their presence on the author list.