Mark 7:1

‘And there gathered together to him the Pharisees and certain of the Scribes who had come down from Jerusalem.'

The fact that these men approached in a body demonstrated the official nature of the investigation. They were there to test His orthodoxy and to find out more about the new expansion of His ministry. The Pharisees, who were relatively few in number but had an importance beyond their numbers as ‘observers and teachers of the Law' (there were altogether around six to seven thousand of them), had called in these Doctors of the Law to support their case against Him. They wanted to discredit Him in front of the people (Mark 7:14), and who better to do it than the experts from Jerusalem.