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> Prosecutors in the US Attorney's office plan to open a federal murder investigation into the death of Brian D. Sicknick, a US Capitol Police officer who died Thursday night, a law enforcement official tells CNN.
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[source](https://edition.cnn.com/2021/01/08/politics/capitol-police-officer-killed/index.html)


I am not a lawyer, not even American, so perhaps someone (who is both) could tidy up this next bit ...


I am aware that American law has a concept of each member of a group being jointly responsible for the actions of other members of the group (could someone please cite the relevant law?).


So, for instance, a getaway driver parked around the corner can be charged with murder if an accomplice kills a bank teller during a robbery.


Could this be applied such that every member of the crowd (or some subset thereof) around the Capitol at the time of the officer's injuries be charged? I realize that this is, in practice, highly unlikely to happen. But I seek to understand to what extend that the could theoretically apply to such a large crowd.



Could all participants of the recent Capitol invasion be charged over the death of Officer Brian D. Sicknick?