The answers to the clues below will have something in common.

1. Pay
2. Tolerate
3. Gist
4. Caught stealing
5. Rush
6. Supply with weapons
7. Identify
8. Support
9. Confront
10. Follow rules
11. Space
12. Accept responsibility
13. Aware of what's going on
14. Frightening
15. Police helicopter
16. Daydreaming

Answers:

1. Foot the bill
2. Stomach
3. Heart of the matter
4. Hand in the till
5. Leg it
6. Arm
7. Finger
8. Back
9. Face
10. Toe the line 
11. Elbow room
12. Shoulder 
13. Ear to the ground
14. Hair-raising 
15. Eye-in-the-sky
16. Head in the clouds