Across:
1 What one of those WAGS (wag = joker) is capable of (HUMOUR) will make you laugh (HUMOUR),
4 A (A-) hit (-BASH-) in (-IN-) Government (-G) (ABASHING) – that’s embarrassing (ABASHING),
9 Left (L-) sweetheart (‘swEet’ heart = -E-) with malaria (-AGUE) (LEAGUE) in lodge (lodge/guild = LEAGUE),
10 Crime fighting organisation (INTERPOL) tip loner (tip loner) off (= anagram indicator) (tip loner = INTERPOL),
12 Latest lie (latest lie) articulated (= anagram indicator) (latest lie = SATELLITE) by one of those dishy types (SATELLITE dish),
13 It’s easy to pick up (LIGHT) what was illuminated (lit = LI-T) outside Grand (-G-) Hotel (-H-) (LIGHT),
14 One of those in March (DEMONSTRATOR) showing the way perhaps (DEMONSTRATOR),
18 Gives the go ahead (TRAFFIC LIGHT) for illegal trade (TRAFFIC) with 13 across (‘light’ = LIGHT) (TRAFFIC LIGHT),
21 No harm in March hare (no ‘harm’ in ‘March hare’ = arche = REACH) to get there? (REACH there),
22 Thoughtfully (HEEDFULLY), in a manner of speaking (= homophone indicator), he’d (‘he’d’ = ‘heed’ = HEED-) get stuffed (-FULL-) turkey from The Foundation (‘turkeY’ from the foundation = -Y) (HEEDFULLY),
24 Devotee (FAN-) has shown a proficiency at judo (-DAN-) and energy (-GO) (FANDANGO) for dance (FANDANGO),
25 Prepare to play (WARM-UP) in heat? (WARM-UP),
26 Employed by laboratory? (TEST TUBE) Save (but) up (= reverse indicator) (but = TUB-) after (= position indicator) ordeal (TEST) and go to Spain! (-E) (TEST TUBE),
27 Record (extended play record = -EP-) by tenor (-T-) included in sequence of songs (set = -S-ET) (SEPTET) produced by a number of singers (SEPTET).
Down:
1 Has an inclination (HILLSIDE) this is for the Dublin supporters (HILL-) and Kerry (-SIDE) (HILLSIDE),
2 Play charades (M-IME) around neat (neat) set (= anagram indicator) (neat = -EANT-) (MEANTIME) in the interval (MEANTIME),
3 Stands up against leaders (‘Stands Up Against’ leaders = -SUA-) in university (University of Limerick = U-L) (USUAL) every day? (every day = everyday = USUAL),
5 Presumably the one running his eye over The Hill (BANK EXAMINER) checking places of interest for what might be outstanding (BANK EXAMINER),
6 Lose towel (lose towel) swimming (= anagram indicator) (lose towel = STEEL WOOL) with cleaner – the abrasive one from household (STEEL WOOL),
7 Take issue with (IMPUGN) question to dispute the truth? (IMPUGN),
8 Delegation dine out (‘delegation’ ‘dine’ out = legato = GELATO) in the Italian parlour (GELATO),
11 Would you have to go to the talking shop for this present (GIFT OF THE GAB) in Blarney? (blarney = GIFT OF THE GAB),
15 What’s the point (compass point NORTHEAST) of Nora (NOR-A-) welcoming article (-THE-) on empty (‘e’) place? (‘set’ without ‘e’ = -ST) (NORTHEAST),
16 Wise guy (sage) loses the head (sage’ without ‘s’ = AGE) – it’s the last straw (LIMIT) (AGE LIMIT) for the bar restricting entry (AGE LIMIT),
17 Doesn’t move (STAYS PUT) remains (STAYS) from place (PUT) (STAYS PUT),
19 Benefit (PROFIT) to university worker (PROF-) in the city centre (in the ‘cITy’ centre = -IT) (PROFIT),
20 Local spooks (HAUNTS) search (hunt = H-UNT-) around area (-A-) with school (-S) (HAUNTS),
23 Shaving (shaving/chip = FLAKE) head for (head ‘For’ = F-) Victoria, for one (-LAKE Victoria) (FLAKE).