Welcome to the forum!
Here are the IIHS safety ratings you can take a look at.
Civic: http://www.iihs.org/iihs/ratings/vehicle/v/honda/civic-4-door-sedan
Accord: http://www.iihs.org/iihs/ratings/vehicle/v/honda/accord-4-door-sedan
Both scored very well in the tests so it may be down to which look you prefer and the mpg.
Here are the IIHS safety ratings you can take a look at.
Civic: http://www.iihs.org/iihs/ratings/vehicle/v/honda/civic-4-door-sedan
Accord: http://www.iihs.org/iihs/ratings/vehicle/v/honda/accord-4-door-sedan
Both scored very well in the tests so it may be down to which look you prefer and the mpg.