Across:
8 Is it a badge of honour (BROOCH) for church (-CH) starting (= positional indicator) witchcraft? (witch craft = broom) Mostly! (m) (‘broom’ without ‘m’ = BROO-) (BROOCH),
9 Supporters meeting (caucus = CAUC-US) about a (-A-) head of state (head of ‘state’ = -S-) (CAUCASUS) in Russia (CAUCASUS),
10 Beats (TOPS) up (= reversal indicator) those characters in Trainspotting (those characters in ‘Trainspotting’ = spot = TOPS),
11 Nine topics (nine topics = INSPECTION) redrafted (= anagram indicator) for examination (INSPECTION),
12 Network (WEB-) mostly (p) for soldiers (“camp” without ‘p’ = -CAM) (WEBCAM) bringing others to view the site (WEBCAM),
14 Reflects (= reversal indicator) music (rap = PAR-) that’s nasty (-ME-AN) about lead singer (lead ‘singer’ = -S-) (PARMESAN) produced by a hard, cheesy type (PARMESAN),
15 Make allowances for (TAKE INTO ACCOUNT) what the bank will do with my money (TAKE INTO ACCOUNT),
18 A-list rum (A-list rum = ALTRUISM) cocktail (= anagram indicator) – is that a measure of public-spiritedness? (ALTRUISM),
20 Master (master = MATERS) flabbergasted (= anagram indicator) by public-school mothers (MATERS),
22 Stock option (CATTLE) and payment for services (FEE-) connected with top drugs (top ‘drugs’ = -D) (CATTLE FEED) and grass (CATTLE FEED),
24 Sample of layer in dermis (sample of ‘layer in dermis’ = RIND) of skin (RIND),
25 Course of action (SCHEME-) for writing (from the 3Rs = -R-) introduction to screenplay (introduction to ‘screenplay’ = -S) (SCHEMERS) for those interested in plot (SCHEMERS),
26 Graduate (-MBA-) tucked into heads, wings or thighs (heads, ‘wings or thighs’ = WO-T) (WOMBAT) of a beastly type from down under (WOMBAT).
Down:
1 A set routine (in a GROOVE) to order (-O-) in a group of trees (grove = GRO-VE) (GROOVE),
2 Gloss over missing grove (‘gloss over’ missing ‘grove’ = lsso = LOSS) – it’s a tax right-off (LOSS),
3 Board members (CHAIRMEN) from Switzerland (CH-) join those on the plane (-AIRMEN) (CHAIRMEN),
4 Makes a scene (ACTS) with Alliance’s (pacts) missing leader (p) (‘pacts’ without ‘p’ = ACTS),
5 Stylish director (AUTEUR) loses head (h) with overbearing arrogance (‘hauteur’ without ‘h’ = AUTEUR),
6 Place to holiday before Day of Judgement (LAST RESORT) – only go if all else fails (LAST RESORT),
7 A (A-) U-Boat (uboat = UTOBA-) built (= anagram indicator) on the banks of haven (on the banks of ‘haven’ = -HN) (AUTOBAHN) by German motorway (AUTOBAHN),
13 Revolutionary (CHE-) takes half of (half of) mine (half of ‘quarry’ = -RRY) and leaves home? (TREE) (CHERRY TREE) That’s bound to bear fruit! (CHERRY TREE),
14 Foreign politician (Prime Minister = P-M) welcomes row (“row” = “roe” = -ROE-) on the radio (= homophone indicator) (PROEM) in the introduction (preface = PROEM),
16 Everyone (ALL-) from island (-I-) goes a fair amount of the (half of) distance (half of ‘distance’ = - ANCE) (ALLIANCE) to party up north (ALLIANCE Party),
17 Loss of face (COMEDOWN) in company (CO-) for medical examiner (-ME) in Ulster (-DOWN) (COMEDOWN),
19 Local diamonds (local ‘diamonds’ = ICE) sourced from China originally (TEA) (ICE TEA) by cool type during the summer (ICE TEA),
21 Organisation (UN-) for women (-W-) consumed by what’s produced by The Sun (ray = R-AY) (RUNWAY) offering a way for those eager to take flight (RUNWAY),
23 Susceptible (EASY) to a piece of cake (EASY),
24 Spirit (RUM-) photography? Tip (‘photography’ tip = -P) (RUMP) – it’s behind you! (RUMP).