Only two steps you need to do:

1. “sudo dpkg-reconfigure wireshark-common” (choose yes to allow Dumpcap to make the wireshark group members able to capture packets)
2. “sudo adduser USERNAME wireshark” to add your user to the wireshark group

Then you just need to logout and back in.

This was tested successfully on Ubuntu 16.04

Enjoy!

Sources:

• https://wiki.wireshark.org/CaptureSetup/CapturePrivileges
• https://anonscm.debian.org/viewvc/collab-maint/ext-maint/wireshark/trunk/debian/README.Debian?view=markup