Connection error when attempting to connect to /dev/ttyACM0 on Ubuntu v14

If i install the the espruino module local and not global it works:

:~/Downloads/espruino$ node node_modules/espruino/bin/espruino-cli.js 
Espruino Command-line Tool 0.0.36
-----------------------------------

Using first port, {"path":"/dev/ttyACM0","usb":[1155,22336],"description":"Espruino board"}
Connecting to '/dev/ttyACM0'
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          |_| http://espruino.com
 1v95 Copyright 2017 G.Williams

>Connected