Solution to 16D has been deliberately left unsolved and is to be answered only by a non-regular / novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.
ACROSS
7 Legal nationalist forces fighting to secure independence (8) FORENSIC {N+FORCES}* over {I}
9 Model saving time for second sibling (6) SISTER SI(-t+s)STER
10 Defeat armoured vehicle (4) TANK [DD]
11 Communicate with men hiring registered vendor (10) CONTRACTOR {CONT{R}ACT}{OR}
12 Doctor separating wounded and serious (6) SOMBRE {SO{MB}RE}
14 Protect Sinner - He's lost (8) ENSHRINE {SINNER+HE}*
15 A scene from Tom & Jerry, possibly in a temporary rally? (4,3,6) DEAD CAT BOUNCE [DD]
18 Shot group of journalists per Spooner (8) BACKHAND (hack band to backhand)
20 Local icon's clothing fabric (6) CALICO [T]
21 Setter in main marketplace (4,6) HIGH STREET {SETTER}* [RA]
22 Field manager regularly clearing sink (4) FLAG {FieLd+mAnaGer}
23 Keep checking elephants on vacation in jungle (6) FOREST {FOR{El...tS}T}
24 Win back in random plan (8) STRATEGY {STRA{GET<=}Y}
DOWN
1 Decline screening said overs set up in camera (8) POLAROID {DI{ORAL}{O}P}<=
3 Tipsy chemist bottling spirit (6) PSYCHE [T]
4 European crowd introduced to very strong coffee (8) ESPRESSO {E}{S{PRESS}O}
5 Rich saloon exercises happening at identical intervals (10) ISOCHRONAL*
6 Pity engineer spoiling Onam (6) BEMOAN {BE}{ONAM*}
8 Vanity firm is sentenced wrongly (13) CONCEITEDNESS {CO}{IS+SENTENCED}*
13 Initially bride needs husband: revolting to go becomes a disgrace to family (5,5) BLACK SHEEP {Br..e}{LACKS}{H}{PEE<=}
16 Virtue of unwinding by a trip to spa which is taken frequently (8) C?A?T?T? {Addendum - CHASTITY {bY+a+TrIp+To+SpA+sHiCh}<= See comments)
17 Trade banter (8) EXCHANGE [DD]
Reference List
Nationalsit = N, Independence = I, Time = T, Second = S, Registered = R, Men = OR, Overs = O, European = E, Firm = CO, Husband = H, To go = PEE
