Across:
1 AHA rip (AHA rip) off (= anagram indicator) (AHA rip = PARIAH) one of The Outcasts (one of the outcasts = PARIAH),
4 Exerted influence on (AFFECTED) Bill (bill/ad = A-D) over special (= anagram indicator) effect? (effect = -FFECTE-) (AFFECTED),
9 Yale is (Yale is) developing (= anagram indicator) (Yale is = EASILY) without difficulty (EASILY),
10 A (A-) marine (marine = -RMENIA-) formation (= anagram indicator) north (-N) (ARMENIAN) of the Caucasus (of the Caucasus = ARMENIAN),
12 Unveil (SHOW) suit (TRIAL) (SHOW TRIAL) – the one put on by Stalin? It doesn’t do justice to those who’ve been fitted up! (SHOW TRIAL),
13 Pulp (PRESS) or Squeeze? (PRESS),
14 Forcibly enlisting (PRESS-GANGING) 13 across (‘press’ = PRESS-) for group of friends (gang = -GANG-) in (-IN-) Government (-G) (PRESS-GANGING),
18 Jack Russell’s relative (IRISH TERRIER) introduces 17 down (introduces ‘Irish Sea’ = IRISH) by Toto (Toto in the “Wizard of Oz” was a TERRIER) (IRISH TERRIER),
21 Leading the pack (AHEAD) in trip out of apartheid (‘trip’ out of ‘apartheid’ = aahed = AHEAD),
22 Performs a number of half-turns (CARACOLES) for Irish friend (Irish ‘friend’ = CARA-) going to Newcastle (coals to Newcastle), as the saying goes (= homophone indicator) (‘coals’ = ‘coles’ = -COLES) (CARACOLES),
24 Fault-finding (CRITICAL) electricians seen leaving (‘electricians’ ‘seen’ leaving/without ‘leaving’ = lctrica = CRITICAL),
25 Madeira’s (Madeira’s wines = DRINKS) ports? (DRINKS),
26 The Fugitive’s (REFUGEES) about (RE-) endless (n) entertainment (‘fun’ without’ n’ = -FU-) and gutless (n) character builders (‘genes’ without ‘n’= -GEES) (REFUGEES),
27 Sympathiser dismisses myths (‘sympathiser’ dismisses ‘myths’ = paiser = PERSIA) of the old country (PERSIA).
Down:
1 Exercises (PRESS-UPS) journalists’ (PRESS-) union (-U-) with pressure (-P-) on society (-S) (PRESS-UPS),
2 Put back in its original condition (RESTORED) by time (-T-) in rose-red (rose red) fluid (= anagram indicator) (rose red = RES-ORED) (RESTORED),
3 Issue (ALLOT) of sorcerer getting off roller coaster (‘sorcerer’ getting off ‘roller coaster’ = ollat = ALLOT),
5 Irish men (Irish ‘men’ = FIR-) taking English (-E-) modes of transport going overseas (barges = -LIGHTERS) (FIRELIGHTERS) to the matches (fire lighters = FIRELIGHTERS),
6 The Observer (EYE-) intro (-OPENER) (EYE-OPENER) is a revelation (EYE-OPENER),
7 No space in police state (no ‘space’ in ‘police state’ = olitte = TOILET) for the gents? (TOILET),
8 Is rather sweet during the break (DANISH pastry) describing Hamlet (DANISH),
11 Cut off (DISASSOCIATE) from detective’s (DI’s = DIS-) sidekick (-ASSOCIATE) (DISASSOCIATE),
15 Slicing (SHREDDING) starter for hummus (starter for ‘Hummus’ = -H-) and Rosé (rose = -RED-) – the top d’Anjou (the top ‘D anjou’ = -D-) – all consumed by Carol! (carol/sing = S-ING) (SHREDDING),
16 Manuscript (manuscript = MS = M-S) covers papers (-ID- papers) lost (-L-) and (-AND-) (MIDLANDS) found in central Ireland (MIDLANDS),
17 In a manner of speaking (IRISH), State (= homophone indicator) view (‘see’ = ‘SEA’) (IRISH SEA) stops some British people running here (IRISH SEA),
19 The German (‘the’ German = D-ER) holding African party (African National Congress = -ANC-) (DANCER) for one who enjoys a number of jigs and reels (DANCER),
20 Contradict (BELIE-) key (music key -F) (BELIEF) judgement (BELIEF),
23 Church (Church of England = CE = C-E) overlooks old city (-UR-) for some initial (‘Some’ initial = -S) (CURSE) bad spell? (CURSE).