diff --git a/tests/test_ers97.py b/tests/test_ers97.py
index 9e091b0..df12fef 100644
--- a/tests/test_ers97.py
+++ b/tests/test_ers97.py
@@ -20,8 +20,10 @@ import pyRCV2.blt
 import pyRCV2.numbers
 from pyRCV2.method.gregory import EGSTVCounter
 from pyRCV2.model import CandidateState, CountCompleted
+import tests.util
 
 import csv
+import json
 
 # Read model CSV
 
@@ -32,7 +34,7 @@ with open('tests/data/ers97.csv', 'r', newline='') as f:
 candidates = [data[i][0] for i in range(2, len(data) - 2)]
 
 @test_steps(*['Stage {}'.format(data[0][i]) for i in range(1, len(data[0]), 2)])
-def test_ers97():
+def test_ers97_py():
 	"""Compare count of ers97.blt with model result computed by hand"""
 	
 	pyRCV2.numbers.set_numclass(pyRCV2.numbers.Fixed)
@@ -84,3 +86,48 @@ def test_ers97():
 			assert result.vote_required_election.pp(2) == votes_required.pp(2), 'Failed to verify votes required for election, got {} expected {}'.format(result.vote_required_election.pp(2), votes_required.pp(2))
 		
 		yield 'Stage {}'.format(stage)
+
+@test_steps(*['Stage {}'.format(data[0][i]) for i in range(1, len(data[0]), 2)])
+def test_ers97_js():
+	ctx = tests.util.init_context()
+	
+	ctx.eval('py.pyRCV2.numbers.set_numclass(py.pyRCV2.numbers.Fixed);')
+	ctx.eval('py.pyRCV2.numbers.set_dps(5);')
+	
+	with open('tests/data/ers97.blt', 'r') as f:
+		election = f.read()
+	ctx.eval('let electionData = {};'.format(json.dumps(election)))
+	ctx.eval('let election = py.pyRCV2.blt.readBLT(electionData);')
+	
+	ctx.eval('let counter = py.pyRCV2.method.gregory.EGSTVCounter(election, { quota: "droop_exact", quota_mode: "ers97", bulk_exclude: true, defer_surpluses: true, round_quota: 2, round_votes: 2, round_tvs: 2, round_weights: 2, papers: "transferable", exclusion: "by_value"});')
+	
+	ctx.eval('let result = counter.reset();')
+	assert ctx.eval('result.quota.__eq__(py.pyRCV2.numbers.Num("107.58"))'), 'Failed to verify quota, got {} expected 107.58'.format(ctx.eval('result.quota.pp(2)'))
+	
+	ctx.eval('let votes, cc, nontransferable, votes_required;')
+	for i in range(1, len(data[0]), 2):
+		stage = int(data[0][i])
+		
+		while ctx.eval('counter.step_results.length') < stage:
+			assert ctx.eval('result = counter.step();')
+		
+		comment = data[1][i]
+		assert ctx.eval('result.comment') == comment, 'Failed to verify comment'
+		
+		for j, cand in enumerate(candidates):
+			ctx.eval('votes = py.pyRCV2.numbers.Num("{}");'.format(data[j + 2][i]))
+			ctx.eval('for (let [c1, cc1] of result.candidates.py_items()) { if (c1.py_name == "' + cand + '") { cc = cc1; } }')
+			assert ctx.eval('cc.votes.__eq__(votes)'), 'Failed to verify candidate "{}" votes, got {} expected {}'.format(cand, ctx.eval('cc.votes.pp(0)'), ctx.eval('votes.pp(0)'))
+			
+			state = data[j + 2][i + 1] if len(data[j + 2]) > (i + 1) else ''
+			accept = {'': CandidateState.HOPEFUL, 'PEL': CandidateState.PROVISIONALLY_ELECTED, 'EL': CandidateState.ELECTED, 'EX': CandidateState.EXCLUDED, 'EXCLUDING': CandidateState.EXCLUDING}
+			assert ctx.eval('cc.state') == accept[state], 'Failed to verify candidate "{}" state'.format(cand)
+		
+		ctx.eval('nontransferable = py.pyRCV2.numbers.Num({});'.format(data[len(candidates) + 2][i]))
+		assert ctx.eval('result.exhausted.votes.__add__(result.loss_fraction.votes).__eq__(nontransferable)'), 'Failed to verify non-transferable votes, got {} expected {}'.format(ctx.eval('result.exhausted.votes.__add__(result.loss_fraction.votes).pp(2)'), ctx.eval('nontransferable.pp(2)'))
+		
+		if data[len(candidates) + 3][i]:
+			ctx.eval('votes_required = py.pyRCV2.numbers.Num({});'.format(data[len(candidates) + 3][i]))
+			assert ctx.eval('result.vote_required_election.pp(2)') == ctx.eval('votes_required.pp(2)'), 'Failed to verify votes required for election, got {} expected {}'.format(ctx.eval('result.vote_required_election.pp(2)'), ctx.eval('votes_required.pp(2)'))
+		
+		yield 'Stage {}'.format(stage)